Salaam , i have few questions to ask from Agha Sahlani sahib,
 if we designate a renovated hall in the building and recite a segha for masjid for the whole hall so can we do those following beside all other restrictions that apply for masjid sanctity . 
1. Can we make or keep azza khana (like taboot and alaams of ghazi Abbas as in the back corner of the hall if we designate the whole hall is majid? And that azza khanaa will be covered by curtains and will not be infront of any persons who is doing prayers anywhere in the hall. 
2. Can  we do majalis e azaa in Muhurran and mattam in the same hall that is desinated as masjid since there is no other place as big to held majalis e azaa. 
3. Can we decorate the back wall of the designated masjid hall with Muharram banners?
Please guide us as soon as possible.
Sincerely
Azhar Naqvi
302-897-3933
New Castle DELAWARE USA.