Love the whole idea and execution, concise and open for exploration by the players and the GM.
And, as I always thought the Rakshasa to be filled with adventure worthy potential, even more with all the interdimensional and cosmic wares and relics that might be in its lair, this aspect is harnessed fully in the module.
The whole portal mechanism and the maps on the last page are awesomely done, genius idea.
Very good work!