The Ajantis BG Expansion Modification is a mod for original ("vanilla") BG(+TotSC), Tutu, Baldur’s Gate Trilogy (BGT), Baldur's Gate Enhanced Edition (BG:EE), and Enhanced Edition Trilogy (EET).
For original BG:TotSC, the mod adds a friendship track and the BG1NPC Project romance for Ajantis. The original BG1NPC Project romance was adjusted slightly with regard to the restrictions of the BG1 engine, although overall the content stayed the same.
For Tutu, BGT, BG:EE, and EET, the mod adds a friendship track and more romance content for the BG1NPC Project romance for Ajantis. Content-wise, the mod is meant as an addition to the BG1NPC Project, but technically it can be installed and played without the BG1NPC Project. If the player started and interrupted Ajantis's BG1NPC Project romance, the friendship sequence should initiate after that depending on how far the romance went. If you do not have the BG1NPC Project installed, the friendship talks become available immediately.
For BG:EE and EET there is a second, independent component with the option to use the existent BG:EE BAM for Ajantis' shield (green dragon on golden ground), if BG1NPC is installed.