Cannot evaluate the expression in left slicing expression Error

I am sharing link to my program. When i execute it I am getting the following error.

**The range of the part select is illegal:
Unknown range in part select.AM_1[i:(i + 7)] //Error-1

Cannot evaluate the expression in left slicing expression.
The expression must be compile time constant. // Error-2**

Here in the program what I need to do is :

I have two 8 bit queues which have fixed values. Now I want to convert them into 10 bit queues and then interleave both queues one by one.

In reply to maitrygandhi:

Please read this thread.