Weird after-tranny service issues

[Messinian900S]

So I got my speedo-gear INSIDE the tranny replaced (to fix no speedo and base boost/running rich ECU condition) and got a new SPEC 2+ clutch in about 2 weeks ago and I have noticed a few things going awry since then.

1- Firstly, the biggest so far, the ABS comes on consistently under LIGHT braking. The ABS works properly when it should (sliding) and doesn't come on from a hard, non-sliding brake...but for some reason when I use light pressure-for instance stopping at a light slowly- it decides to come on and I get the sensation of sliding/rolling then it grips suddenly and I jerk forward. Never did this before the repair work. And no dash lights are on for ABS or anything really. Any ideas?

2- The clutch pedal actuation felt fine for about a week or so then I noticed that the pedal was starting to delay on returning to its normal position from a push. It's now becoming quite irritating and making driving a pain. It seems like a master cylinder issue (crack letting air in?) or maybe a return spring? Or maybe it just wasn't bled right or enough?

The odd part is I never had either of these problems pre-repair. Now, relatively suddenly, I was told I need to replace the axle (apparently because the ABS tone ring might be damaged?) to fix the ABS issue and also the master cylinder as I was told that the clutch hydro system "self-bleeds" so bleeding issues shouldn't be the problem.

Any insight would be helpful. Honestly, I don't want to immediately accuse the shop of messing things up, but since I paid quite a pretty penny to get this work done, I don't want to spend anymore on fixing issues that may not be my car's fault.

One last thing, I also had a poly tranny bushing put in and also replaced the front lower motor mount (with solid rubber) as mine was broken. There is a now a lot of vibration, more than I would have expected from just a poly bushing swap, and was now told that the rear lower mount is broken which is causing a lot of the issue. I already have a solid rubber one on order, but does anyone know if this will actually fix it or does the poly tranny mount just make things that much worse than stock?