Welcome to NeuroTalk:

I wouldn't increase R-lipoic any further. You are already taking high doses of what is in that supplement. R-lipoic is very potent, and the best version of old ALA. You don't need massive doses of it. With time it may cause a biotin deficiency...and that is because the transporter for it is also used by biotin. So adding in some biotin at a different time of day, may be helpful.

I would however consider supplements that are known to improve axon healing (where the nerves are compressed).

That would be Omega-3 fatty acids, which work with the B12, folate and B6 to remyelinate nerve sheaths. 3 fish oil daily with food, or two Krill oil regular strength, may help alot. Also this has anti-inflammatory actions.

Also I'd look into choline if you don't eat egg yolks, as choline is a major ingredient in membrane repair.

That product you are using, has to be taken on an empty stomach as two ingredients are affected by the presence of food.

I'd also make sure you are getting a quality absorbable magnesium in
your diet, or supplement at 1/2 the RDA..with a chelate (not OXIDE which is not absorbed). Magnesium can be low in many people and it
blocks the NMDA pain receptor, and also is involved with lipid metabolism to help repair nerve functions. It will also reduce some muscle tightness/spasms/twitching.
Here is more information on magnesium:
http://neurotalk.psychcentral.com/thread1138.html