I might be misunderstanding the nature of the question. It seems you want to work with subscripted variables in a situation where some subscript parts denote independent variables? If so, I would suggest separating into two steps.
(1) Use code that does not fight with the program, e.g. explicit functional dependence such as w[t+2]
instead of a subscripted form thereof. So one of the equations might be c[1,t]+b[2,t+1]==w[t]
(2) After getting code that works, worry about reformatting with subscript notation, e.g. for purposes of presentation, if this is something you need to do.