I tried making a form resizer and it was a major undertaking...

Rich text fields pose some difficulty since they use HTML tags.  To resize font sizes, you need to go inside the font tags and edit the size attributes -- tricky to automate with VBA.

Lines are a problem too, as their thickness only has a limited range.  You have to check if it reaches the upper or lower limit, and also scale it properly with resizing.

Tab controls are a pest as usual, since unopened tabs are inaccessible to VBA, thus impossible to resize what is contained within.

Datasheets pose a special problem: the ColumnWidth property could have the value of -1, which means auto-fit.  If it's -1, you have no way to know what the real width is, so you can't resize it.

These are just a few of the many lovely problems this project produces.