Its not a trick. We use Sliing AND ccbill to track all sales and ccbill send out your check, what's your affiliate ID so I can send you your stats.
Lots of affiliate programs use Sliing, they can also verify this.
The exit popup was only there for a month and did NOT interfere with affiliate sessions.
You can skype or email me with any further questions that might have.
Have a great day!