We're glad to report this has been resolved! We had to make a fundamental change under the hood for this one:

Up until now, when a donation comes in via GoCardless it's immediately marked as complete. But now, it's marked as pending, and we wait for the webhook to confirm whether the donation succeeded or failed before we mark it. This requires no work on your part, but if you see a donation in a pending state, that's why.

Please update to Give GoCardless 1.3.8 and let us know if you run into any further issues.

Our development team will look into this, based on the number of reports we're seeing.