A couple of years ago I made a replacement for BMouse to fix the issues it has with jerky mouse movement for lower mouse sensitivities. I see there are still threads about BMouse issues so I thought I'd post this. I want to believe I posted about this here before but the forums say I have no posts or they're too old. Wanted to play some Blood again but the newer engines couldn't migrate my saves and then I also found this thing I wrote wasn't actually built properly so I dug up the TURBOC compiler and repackaged it.

It works as a drop-in replacement for BMOUSE.EXE, just replace it with SMOUSE.EXE as external program in the setup and the GoG DOSBox conf files. The launch parameters are the same.
Both BMouse and the original tool does an integer division on the raw mouse data, throwing away the remainder. This program will save the remainder and use it again for the next calculations. This removes much of the jerkiness/bumpiness/threshold feeling that you have to move the mouse real fast to make it register.

Downloads:
bitbucket.org/rwesterlund/smouse/downloads/
(need to figure out a way to post a link without getting my post rejected)