Referon can accept any variables in your trackers.
The most common 9 variables are found in Reports - General as separate columns:
- var1
 - var2
 - var3
 - var4
 - var5
 - subid
 - pubid
 - clickid
 - click_id
 
However, if you are using anything outside of these, such as ‘webmasterid’, this can be collected in the ‘other’ the 10th column in dynamic variables group.
Note: if you are using postbacks, ensure the variable matches to your callback url requirements.