I want to use an external sales page but still use the Affiliate feature in Thinkific and figured a way to do so by using a bit of HTML in my course builder to redirect visitors to my external page.
What I did was set up a Private and Hidden course on my Thinkific site which is completely empty. In the Page Code section, I added a bit of HTML which would redirect visitors to my actual sales page:
<meta http-equiv="refresh" content="0; url=www.salespage.com">
This prevents students from seeing my Thinkific landing page and instead, they'll be redirected to my external sales page.
Once I published the course, my affiliates can give out affiliate URL's from Thinkific but it'll redirect visitors to my actual sales page. On my sales page, I link back to the checkout page in Thinkific so when students make the purchase, since they originally started my Thinkific site, they'll be tagged to the affiliate and the sale will be linked my affiliate while still using my external sales page!