some way to always enforce force zero crossing?

Hello.
I'm currently working on a looping-type guitar patch.
I have several waveform displays set to a buffer or two that I am using to select small portions of what I've recorded into the buffer. The waveforms are all set to snap to zero-crossings, and that part is working great. Of course, when I try to record new material into the buffer while keeping the waveform selections as they were, they no longer line up with zero-crossings (unless I reset them) and will pop and click as expected. It's still a work in progress, but I'm hoping to be able to create somewhat seamless textures that can be changed at will as I record new guitar stuff in (activated via footswitch).
Any ideas for fixing this?

Here's the patch if you need it. Thanks!