That's bull***t!!!
F700 and U900 are NOT supported yet by NsPro.
So how did you damaged IMEI "after unlocking with NsPro" on this models?
G800 and U700 unlocking work perfectly on NsPro and there is no way to damage IMEI by unlocking.
Also, there are thousends of nspro users that unlocked G800 and U700 phones, and you are the only one reporting this problem.
Dont you think that's strange?
Beside, is very easy to write IMEI on this models as @ringtons posted:
So if you whant to get some real help, PLZ post the truth and you'l have some chanses to repair that phones.