Suggestions

Post the new log from this crash.

Make sure you are using 64 bit java. "java -version" (without the quotes) from the commandline will say 64-bit if it is; i.e:  

I am trying to boot my Minecraft forge server however it keeps crashing, I tried to allocate more RAM however when I create the.bat file (Start.bat) with the line inside(java -Xmx4G -Xms1G -forge server .jar nogui). I launch it and it crashes straight away. Please Help Me ASAP, Best Wishes Jake

You might be able to do this by using the RenderPlayerEvent and/or replacing the player's model

Look at usages of the method to find out.