I would like to run mo creatures to back before they combined the vanilla horses and mo creatures horses, and after creating a new minecraft in the launch options for version 1.5.2, the game will start up and stay on the Mojang logo for a minute, and then show me a crash report in which it says everytime :
Minecraft has crashed!
----------------------

Minecraft has stopped running because it encountered a problem; Failed to start game

A full error report has been saved to C:\Users\shayl\AppData\Roaming\.minecraft\crash-reports\crash-2017-06-07_21.31.23-client.txt - Please include a copy of that file (Not this screen!) if you report this crash to anyone; without it, they will not be able to help fix the crash

— BEGIN ERROR REPORT acedb7e0 --------
Full report at:
C:\Users\shayl\AppData\Roaming\.minecraft\crash-reports\crash-2017-06-07_21.31.23-client.txt
Please show that file to Mojang, NOT just this screen!

Generated 6/7/17 9:31 PM

– System Details –
Details:
Minecraft Version: 1.5.2
Operating System: Windows 10 (amd64) version 10.0
Java Version: 1.8.0_25, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 45136008 bytes (43 MB) / 127139840 bytes (121 MB) up to 1060372480 bytes (1011 MB)
JVM Flags: 6 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
AABB Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
Suspicious classes: No suspicious classes found.
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
LWJGL: 2.9.0
OpenGL: AMD Radeon R9 200 Series GL version 4.5.14008 Compatibility Profile Context 21.19.137.514, ATI Technologies Inc.
Is Modded: Very likely; Jar signature invalidated
Type: Client (map_client.txt)
Texture Pack: Default
Profiler Position: N/A (disabled)
Vec3 Pool Size: ~_ERROR~ NullPointerException: null

java.lang.NullPointerException
at java.io.Reader.<init>(Reader.java:78)
at java.io.InputStreamReader.<init>(InputStreamReader.java:97)
at bp.a(SourceFile:64)
at bp.a(SourceFile:100)
at net.minecraft.client.Minecraft.a(SourceFile:252)
at avv.a(SourceFile:56)
at net.minecraft.client.Minecraft.run(SourceFile:507)
at java.lang.Thread.run(Thread.java:745)
— END ERROR REPORT 2ff8da0 ----------
It is not a forge version, because to run the forge version I must first run 1.5.2 at least once. Which obviously, I'm unable to do. I did not provide an attachment to the above mentioned folder because, alas, I really don't think it has the answer. Thankyou