Yes it is!
Design Palette Pro is compatible with a multisite installation. However, it should not be activated at the network level, rather, activate it on each individual site you’d like to use it on. Due to the nature of how networks are set up, each site within the network will require its own license key.
Have a large network? In some special cases we have set up a way to treat a network as a single site for licensing / updates / upgrades, but those are done on a case by case basis and have different pricing in place. Please contact us if this is something you’d like to explore.