I recreated a downloaded world from mcschematics. i played for ten to fifteen minutes but then it crashed giving me this error.

[10:58:21 INFO]: Client>
[10:58:21 INFO]: Client> [10:58:21] [Sound Library Loader/INFO]: Sound engine started
[10:58:21 INFO]: Client> [10:58:21] [Client thread/INFO]: Created: 512x256 textures/blocks-atlas
[10:58:21 INFO]: Client> [10:58:21] [Client thread/INFO]: Created: 256x256 textures/items-atlas
[10:58:21 INFO]: Client> [10:58:21] [Client thread/ERROR]: ########## GL ERROR ##########
[10:58:21 INFO]: Client> [10:58:21] [Client thread/ERROR]: @ Post startup
[10:58:21 INFO]: Client> [10:58:21] [Client thread/ERROR]: 1281: Invalid value
[10:58:21 INFO]: Client> [10:58:21] [Client thread/ERROR]: ########## GL ERROR ##########
[10:58:21 INFO]: Client> [10:58:21] [Client thread/ERROR]: @ Pre render
[10:58:21 INFO]: Client> [10:58:21] [Client thread/ERROR]: 1281: Invalid value
[10:58:24 INFO]: Client> [10:58:24] [Server thread/INFO]: Starting integrated minecraft server version 1.7.5
[10:58:24 INFO]: Client> [10:58:24] [Server thread/INFO]: Generating keypair
[10:58:25 INFO]: Client> [10:58:25] [Server thread/INFO]: Preparing start region for level 0
[10:58:26 INFO]: Client> [10:58:26] [Server thread/INFO]: ChrispyT2[local:E:11ea1c0e] logged in with entity id 10 at (-448.0640721150295, 84.64716019861498, 18.2187534282247)
[10:58:26 INFO]: Client> [10:58:26] [Server thread/INFO]: ChrispyT2 joined the game
[10:58:28 INFO]: Client> [10:58:28] [Server thread/ERROR]: Encountered an unexpected exception
[10:58:28 INFO]: Client> s: Exception ticking world
[10:58:28 INFO]: Client> at net.minecraft.server.MinecraftServer.v(SourceFile:508) ~[1.7.5.jar:?]
[10:58:28 INFO]: Client> at net.minecraft.server.MinecraftServer.u(SourceFile:443) ~[1.7.5.jar:?]
[10:58:28 INFO]: Client> at btq.u(SourceFile:117) ~[1.7.5.jar:?]
[10:58:28 INFO]: Client> at net.minecraft.server.MinecraftServer.run(SourceFile:359) [1.7.5.jar:?]
[10:58:28 INFO]: Client> at lh.run(SourceFile:618) [1.7.5.jar:?]
[10:58:28 INFO]: Client> Caused by: java.lang.IllegalArgumentException: n must be positive
[10:58:28 INFO]: Client> at java.util.Random.nextInt(Random.java:250) ~[?:1.6.0_65]
[10:58:28 INFO]: Client> at agx.a(SourceFile:122) ~[1.7.5.jar:?]
[10:58:28 INFO]: Client> at agx.a(SourceFile:27) ~[1.7.5.jar:?]
[10:58:28 INFO]: Client> at agr.a(SourceFile:364) ~[1.7.5.jar:?]
[10:58:28 INFO]: Client> at aha.a(SourceFile:42) ~[1.7.5.jar:?]
[10:58:28 INFO]: Client> at apw.a(SourceFile:432) ~[1.7.5.jar:?]
[10:58:28 INFO]: Client> at mr.a(SourceFile:165) ~[1.7.5.jar:?]
[10:58:28 INFO]: Client> at aou.a(SourceFile:778) ~[1.7.5.jar:?]
[10:58:28 INFO]: Client> at mr.c(SourceFile:100) ~[1.7.5.jar:?]
[10:58:28 INFO]: Client> at mr.d(SourceFile:113) ~[1.7.5.jar:?]
[10:58:28 INFO]: Client> at afy.e(SourceFile:309) ~[1.7.5.jar:?]
[10:58:28 INFO]: Client> at ms.g(SourceFile:233) ~[1.7.5.jar:?]
[10:58:28 INFO]: Client> at ms.b(SourceFile:136) ~[1.7.5.jar:?]
[10:58:28 INFO]: Client> at net.minecraft.server.MinecraftServer.v(SourceFile:504) ~[1.7.5.jar:?]
[10:58:28 INFO]: Client> ... 4 more
[10:58:28 INFO]: Client> [10:58:28] [Server thread/ERROR]: This crash report has been saved to: /Users/Turnbulls/Library/Application Support/minecraft/crash-reports/crash-2014-04-05_10.58.28-server.txt
[10:58:28 INFO]: Client> [10:58:28] [Server thread/INFO]: Stopping server
[10:58:28 INFO]: Client> [10:58:28] [Server thread/INFO]: Saving players
[10:58:28 INFO]: Client> [10:58:28] [Server thread/INFO]: Saving worlds
[10:58:28 INFO]: Client> [10:58:28] [Server thread/INFO]: Saving chunks for level 'Airport'/Overworld
[10:58:28 INFO]: Client> ---- Minecraft Crash Report ----
[10:58:28 INFO]: Client> // Surprise! Haha. Well, this is awkward.
[10:58:28 INFO]: Client>
[10:58:28 INFO]: Client> Time: 4/5/14 10:58 AM
[10:58:28 INFO]: Client> Description: Exception ticking world
[10:58:28 INFO]: Client>
[10:58:28 INFO]: Client> java.lang.IllegalArgumentException: n must be positive
[10:58:28 INFO]: Client> at java.util.Random.nextInt(Random.java:250)
[10:58:28 INFO]: Client> at agx.a(SourceFile:122)
[10:58:28 INFO]: Client> at agx.a(SourceFile:27)
[10:58:28 INFO]: Client> at agr.a(SourceFile:364)
[10:58:28 INFO]: Client> at aha.a(SourceFile:42)
[10:58:28 INFO]: Client> at apw.a(SourceFile:432)
[10:58:28 INFO]: Client> at mr.a(SourceFile:165)
[10:58:28 INFO]: Client> at aou.a(SourceFile:778)
[10:58:28 INFO]: Client> at mr.c(SourceFile:100)
[10:58:28 INFO]: Client> at mr.d(SourceFile:113)
[10:58:28 INFO]: Client> at afy.e(SourceFile:309)
[10:58:28 INFO]: Client> at ms.g(SourceFile:233)
[10:58:28 INFO]: Client> at ms.b(SourceFile:136)
[10:58:28 INFO]: Client> at net.minecraft.server.MinecraftServer.v(SourceFile:504)
[10:58:28 INFO]: Client> at net.minecraft.server.MinecraftServer.u(SourceFile:443)
[10:58:28 INFO]: Client> at btq.u(SourceFile:117)
[10:58:28 INFO]: Client> at net.minecraft.server.MinecraftServer.run(SourceFile:359)
[10:58:28 INFO]: Client> at lh.run(SourceFile:618)
[10:58:28 INFO]: Client>
[10:58:28 INFO]: Client>
[10:58:28 INFO]: Client> A detailed walkthrough of the error, its code path and all known details is as follows:
[10:58:28 INFO]: Client> ---------------------------------------------------------------------------------------
[10:58:28 INFO]: Client>
[10:58:28 INFO]: Client> – Head –
[10:58:28 INFO]: Client> Stacktrace:
[10:58:28 INFO]: Client> at java.util.Random.nextInt(Random.java:250)
[10:58:28 INFO]: Client> at agx.a(SourceFile:122)
[10:58:28 INFO]: Client> at agx.a(SourceFile:27)
[10:58:28 INFO]: Client> at agr.a(SourceFile:364)
[10:58:28 INFO]: Client> at aha.a(SourceFile:42)
[10:58:28 INFO]: Client> at apw.a(SourceFile:432)
[10:58:28 INFO]: Client> at mr.a(SourceFile:165)
[10:58:28 INFO]: Client> at aou.a(SourceFile:778)
[10:58:28 INFO]: Client> at mr.c(SourceFile:100)
[10:58:28 INFO]: Client> at mr.d(SourceFile:113)
[10:58:28 INFO]: Client> at afy.e(SourceFile:309)
[10:58:28 INFO]: Client> at ms.g(SourceFile:233)
[10:58:28 INFO]: Client> at ms.b(SourceFile:136)
[10:58:28 INFO]: Client>
[10:58:28 INFO]: Client> – Affected level –
[10:58:28 INFO]: Client> Details:
[10:58:28 INFO]: Client> Level name: Airport
[10:58:28 INFO]: Client> All players: 1 total; [mv['ChrispyT2'/10, l='Airport', x=-448.06, y=84.65, z=18.22]]
[10:58:28 INFO]: Client> Chunk stats: ServerChunkCache: 1073 Drop: 0
[10:58:28 INFO]: Client> Level seed: 3919725669121290240
[10:58:28 INFO]: Client> Level generator: ID 00 - default, ver 1. Features enabled: true
[10:58:28 INFO]: Client> Level generator options:
[10:58:28 INFO]: Client> Level spawn location: World: (0,65,0), Chunk: (at 0,4,0 in 0,0; contains blocks 0,0,0 to 15,255,15), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
[10:58:28 INFO]: Client> Level time: 20140 game time, 7629 day time
[10:58:28 INFO]: Client> Level dimension: 0
[10:58:28 INFO]: Client> Level storage version: 0x04ABD - Anvil
[10:58:28 INFO]: Client> Level weather: Rain time: 65297 (now: false), thunder time: 158434 (now: false)
[10:58:28 INFO]: Client> Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: true
[10:58:28 INFO]: Client> Stacktrace:
[10:58:28 INFO]: Client> at net.minecraft.server.MinecraftServer.v(SourceFile:504)
[10:58:28 INFO]: Client> at net.minecraft.server.MinecraftServer.u(SourceFile:443)
[10:58:28 INFO]: Client> at btq.u(SourceFile:117)
[10:58:28 INFO]: Client> at net.minecraft.server.MinecraftServer.run(SourceFile:359)
[10:58:28 INFO]: Client> at lh.run(SourceFile:618)
[10:58:28 INFO]: Client>
[10:58:28 INFO]: Client> – System Details –
[10:58:28 INFO]: Client> Details:
[10:58:28 INFO]: Client> Minecraft Version: 1.7.5
[10:58:28 INFO]: Client> Operating System: Mac OS X (x86_64) version 10.9.2
[10:58:28 INFO]: Client> Java Version: 1.6.0_65, Apple Inc.
[10:58:28 INFO]: Client> Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Apple Inc.
[10:58:28 INFO]: Client> Memory: 2069156752 bytes (1973 MB) / 2282749952 bytes (2177 MB) up to 4277534720 bytes (4079 MB)
[10:58:28 INFO]: Client> JVM Flags: 2 total; -Xmx4096M -Xms2048M
[10:58:28 INFO]: Client> AABB Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
[10:58:28 INFO]: Client> IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
[10:58:28 INFO]: Client> Profiler Position: N/A (disabled)
[10:58:28 INFO]: Client> Vec3 Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
[10:58:28 INFO]: Client> Player Count: 1 / 8; [mv['ChrispyT2'/10, l='Airport', x=-448.06, y=84.65, z=18.22]]
[10:58:28 INFO]: Client> Type: Integrated Server (map_client.txt)
[10:58:28 INFO]: Client> Is Modded: Probably not. Jar signature remains and both client + server brands are untouched.
[10:58:28 INFO]: Client> #@Unable to render embedded object: File (@# Game crashed) not found. Crash report saved to: #@!@# /Users/*****/Library/Application Support/minecraft/crash-reports/crash-2014-04-05_10.58.28-server.txt
[10:58:28 INFO]: Client> AL lib: (EE) alc_cleanup: 1 device not closed
[10:58:28 ERROR]: Game ended with bad state (exit code 255)
[10:58:28 INFO]: Crash report detected, opening: /Users/*****/Library/Application Support/minecraft/crash-reports/crash-2014-04-05_10.58.28-server.txt
[10:58:28 INFO]: Ignoring visibility rule and showing launcher due to a game crash
[10:58:28 INFO]: Deleting /Users/******/Library/Application Support/minecraft/versions/1.7.5/1.7.5-natives-1396709898618420000
[10:58:28 INFO]: Reported crash to Mojang (ID 0)