I have come to level 5. I will beat it one day though
Yes, there are small graphical glitches in some stages. Don't remember which ones. But I wouldn't thought about those glitches if you hadn't told about them. They reminds of those glitches you mentioned earlier. But I can't tell for sure they are the same. I think these glitches are more sublime than the ones in for example Pop n twinbees second stage. I will play more tomorrow and do some report.
You should play to stage 4. It's very cool use of Mode7 effects