When in Dimensions please do the following:
Click the Financials Tab
Select Auto Bank Reconciliation
When in the Auto Bank Reconciliation screen, enter a Statement Ref. Number (if you're looking to only make a template, put anything as the reference).
Once entered a reference a few options should be no longer greyed out. On the right-hand side, near the "unreconciled" and "reconciled" tabs you should see a small white page icon (3rd from the right) click this to open the options window.
Click Import Formats
Click the Blank page icon
Give the Import template a name within the "import name" field
Change the import type to the file type you want (if excel, keep as Comma Separated Values)
You now need to select the columns which ABR Field will correspond with the data being imported. For example, The balance of all the transactions within the statement fall within the D column of the Excel sheet. This would be Column number 4 (The order of the letter within the alphabet equals the number the column is).
To enter a number click the ABR field, on the right hand side should see "Separated Values" and it's asking for the Column No. you would put 4 here (or the respective column number).
Once you have filled in the column numbers.
Press the Save button
Import your CSV file as you would normally import a bank statement.
Select your template you just created
Check the information is in the correct column
If the information is not in the correct columns, you will need to go back to the steps listed above, and check the column numbers you have assigned.