I've actually made a quilt before but it was a long time ago and I wanted to check I wasn't blindly making mistake I didn't know I'd made before. (Or making new ones. I'm so innovative.) I also have a few errors in this quilt top, in spite of all my careful cutting and sewing - puckering in the triangles, a bit of a waist in some rows and slightly wobbly edges - and wanted to know if there were any techniques for correcting these. It was surprisingly hard to dig up some solid support. Nearly everything I found was to do with tension issues while quilting, troubleshooting machines and such.
I discovered this forum, reassuringly full of people who have also had similar problems (hurrah!). These guys mostly recommended steaming, which I've already tried and I'm concerned that I'm overcooking parts of the white patterned fabric and it's colouring yellow. Maybe some fabric between iron and quilt would do, but I've already tried setting it a bit. These errors aren't that huge and may not even really show up once the batting is there...
Some recommended "quilting it out" which is to quilt heavily in the area to reduce any visible puckering.
What that discussion did share, however, was this awesome tutorial on realigning blocks and borders: Sharon Schamber's Beginning Quilter : Magical Basting p1.
This, alone, was worth the time spent looking online.