Is there compatibility of the speedrun mod for 1.8.3? I want to run the set seed glitched category and duping items is easier on 1.8-1.8.3. The problem of 1.8 though is that the sheep needed for the wool does not spawn. My Computer cannot run the special timer.

minecrafttimer2.exe should run with no problem, and I don't know about the speedrun mod, I'd suggest you contacted the person who developed if you tried to install it in 1.8.3 and it didn't work. I think it's only for 1.8 though.