Hi @yiga2 - as an update, customizing background color of cells in Table should now be possible in both Retool Cloud, and the latest Retool self-hosted release (version 3.6). Check out @AnsonHwang's comment here describing how to do this using item
Trying this out in a sample app on my side, I can show alternating grey and white cells within a column using {{ item % 2 == 0 ? 'gray': 'white'}} in the Appearance > Background settings of the ID column:
Hopefully by doing this at the columns-level, this helps get you closer with new Table to the functionality you had with the legacy Table component!