General Limitations

These are permanent constraints of how Office itself stores table styles, not bugs in this app.

Cell padding isn't part of a PowerPoint or Excel style

Neither PowerPoint nor Excel store cell padding as part of a table style: PowerPoint treats it as a per-table setting, and Excel's table style format has no cell-margin concept at all.

This app doesn't save cell padding changes for PowerPoint or Excel files. See Editing cell padding.

Gradient and pattern fills aren't supported

Only solid fills (or no fill) can be designed here. If a style already has a gradient or pattern fill from elsewhere, this app preserves it untouched rather than destroying it, but you can't create or edit one.

Row height isn't a style property

Row height is set per table, not per style, in all three applications - there's nothing to design here for it.

The preview panel's checkboxes are display-only

Header row, Total row, Banded rows, and the other preview checkboxes don't get saved - they only control what you see while previewing. See The preview panel for the full explanation, and Setting a default style for the setting that does get saved (which style a new table uses).