I've had all sorts of problems with my legs ranging from night cramps, various tingling sensations, numbness and my blood vessels sometimes feeling like a central heating system full of air, gurgling almost comically. There are lots of suspects and I have tried many remedies but, drinking plenty of water and cycling gives best results.
I started leg and calf stretching exercises, using a rower and walking and all help, but don't cure. Cycling on an exercise bike however works well maybe because it works the muscles and improves blood flow but not under a heavy load like they are when walking. They are not having to cope with my body weight. It all does seem to be more to do with circulation than nerve damage. I lost a lot of weight and started walking more but, surprisingly, it did not prevent things, just improved it a bit. I haven't had any problems since I started cycling though, and drinking water. It's easy to forget to drink enough fresh water.
If you can't get hold of a bike, they are always in charity shops, or don't have the space for one, try swimming. Same idea, no weight on your legs but rythmic movement to get things opening up and the blood flowing.