I don't buy it
KF, I understand your fears, but let's take it from the top....
You seem to feel that your only recourse is pulling a runner... I disagree.
If you read the labour law, you will see that you are actually entitled to leave without notice if they haven't paid you in 3 months, and with no penalties... furthermore, they can't ban you for this either...
You see, this is how low rent employers treat third world illiterate construction workers and they're betting on the fact that they can't read or don't have the time to read... This miserable company is taking the same approach with you... except that you're not illiterate... and in addition to venting here.... take action against them...
Take time to consult an attorney and find out what your rights are and be sure to document EVERYTHING....
Trust me... it's not as difficult to leave that dirtbag outfit as they claim it is... and even more importantly... don't sacrifice your professional integrity for these people... remember, professionals get paid for their work... you are doing the work and not getting paid....
Time to wise up.... why should they ever pay you if you keep coming back and working for free?