Solidworks Blocks blowing up

[AustinSchuh]

A little background: I'm creating a couple gearboxes for a class, so to make it easy to modify everything, I've placed the main sketch in a block which I import into each gearbox plate. This makes things easy to line up, and change, and all sorts of good stuff like that. I'm using Solidworks 2010-2011, education edition.

Unfortunately, sometimes when I change something in the block, some of the relationships in the sketches that include the blocks will randomly switch from, for example, the center of one circle to the center of another circle. As you can imagine, this breaks the sketch horribly, and takes a bit of work to fix each time. This takes a feature that is saving me quite a bit of time and making things easy to maintain, and makes it a lot harder to use.

Does anyone have any idea about what's happening? From everything I know, I'm doing things right and this looks like a bug in Solidworks, but I can't say that for certain, and even if it is a bug, I don't know how to get it fixed. It's easy to reproduce (unfortunately), so I can provide screenshots if that would help explain what's happening. Or models.