Hi Kevin. Ok, this is going to read a bit long winded, but its an easy fix.
TCS M4 decoder had a slight 'surge' problem when BEMF is on. When reducing throttle steps from 28 down the loco would slow accordingly for each step, but when passing down through throttle step 23 or 24, the loco would slightly speed up again (i.e. surge), and then slow as you continued to step down past step 22 and below. This effectively put a what looked bump in the speed curve irrespective of the setting of CV6 (mid voltage), or even if you had proper user speed curve defined. This is a know issue with the TCS that the Laisdcc inherited which was caused by a bug in TCS's implementation of BEMF, but it is a non-issue because you can either turn BEMF off (CV61=0), or better still configure BEMF to be only on from speed steps 1-12 (CV61=1 & CV10=12). Problem cured but you still have ultra smooth BEMF at low speeds, startup, and stopping.
MM141/181 locos never had independent control of the headlamp. It is on at the same time as the fwd white running lights and therefore does not have its own function. F0 turns all lights on or off on 141/181, and they change direction automatically. The switches are for DC operation or consists. With DCC on 141/181 you wont need to change the switches. However the 071/201 do have separate functions for the head lamp, and cab lights (F0=directional running lights, F4=head lamp, F8=cab lights). So you can't turn the head light off on an MM141/181 entering a station unless you also turn off the running lights.