FMod - Grid size inconsistency fix

While using Abiathar to make some of my own levels today, I noticed a small bug. I enabled the grid to see tile boundaries in the simultaneous tileset, but the grid was too fine: 16x16, even though I had zoomed the tileset to a tile size of 32x32. The grid size was appropriate for the level viewer, though. Apparently I missed a spot when giving the simultaneous tileset its own zoom level. This is fixed now.