Use the following as filter in condition part of query
=[Forms]![Form Name].[Filter Field name]
This will filter query to Form Name and shown Filter Field name.
The table structure and your nomenclature is not clear to me. You need to put all value of your calculation fields to one query and than calculate opening balance. you can also do it via VBA.
You can set the [TempVars]![PopUp] as after upupdate property of pop up. Create the query filter on [TempVars]![PopUp]. That way when pop up changes [TempVars]![PopUp] changes and query data modify and hence form update.
Add the column fields in a query and show that additional field as row in Cross tab. i am using this method successfully. eg col =1 ,col 2=3 col3=5 Total:Col1+col2+col3 . show Total in cross tab as row.
You need to prepare a update query where two column value are = to each other. The checkbox is updated to Yes for records where two column value are equal.