probably one of the patches being applied to the dsdt is causing the issue.
you might have to patch then test the dsdt till you find the patch thats affecting trackpad.
you also need to find out who makes the trackpad and find the kext that suits that manufacturer.
the trackpad might be seen as a mouse not a trackpad in osx. which might be why it "works"
if you save both the patched DSDT.aml and the stock one as a DSDT.dsl you can run them through a text compare tool to see the differences.