You can use the Button Creator Pro with E-Junkie. Here is how.
1. Login in to E-Junkie and click on View/Edit/Delete Products
2. Click Get Button Code
3. Copy the href portion of the button code. From the image below I selected https://www.e-junkie.com/ecom/gb.php?c=cart&i=1161144&cl=217551&ejc=2
4. Put the E-Junkie href into the url attribute of the Button Creator Pro shortcode and save.
5. That’s it. Your button should work correctly now.