in reply to Not getting this assignment ...

hashCellID is a HASHES OF ARRAYS data structure. Typically, it would be declared as:
my %hashCellID;

For debugging purposes, you can print the contents of your variables using Data::Dumper:

use Data::Dumper; print Dumper(\%hashCellID);

On a side note, you should post code inside code tags: Writeup Formatting Tips