More curtain models:
https://3dsky.org/collection/shared/5249944 
https://3dsky.org/collection/shared/5452447 

Collection of light-filtering roller blinds
The fabric color can be easily changed in Corona Color
5 blinds of different widths - 2500/2000/1500/1000/750 mm
The length of all blinds is 2500 mm, easily editable to another size.

3dsmax 2013 file and FBX with Corona materials
All materials are CoronaLegacyMtl, compatible with older versions of Corona