Hi there,
I was using this module.
I realized that product points were not properly assigned, after adding and removing product features.
In fact there is a small error in the code in the function uc_userpoints_product_uc_product_feature.
The 'delete' array key doesn't invoke the correct function (uc_userpoints_product_uc_feature_delete).
Instead it invoke uc_userpoints_product_feature_delete, that's wrong.
I hope it helps