Doesn't work properly with custom Launchpad values for rows and columns

[ralph303]

I use a 10 x 8 layout for my launchpad and then Launchpadder only displays 56 apps on each page instead of 80.

To reproduce the bug, these are the values I use:
defaults write com.apple.dock springboard-columns -int 10
defaults write com.apple.dock springboard-rows -int 8

[davidsouza]

I have this same issue