I've built a few landers using the MEM part, and I'm a bit perplexed by it. On it's own, it has a built in fuel tank. But if you try and put any kind of engine on it, you get a big 1.875m "skirt" that appears and apparently you can't get rid of. So you have to either live with it, or make it look more aesthetically pleasing by adding a medium sized tank. Even with the smallest such tank, this gives the lander a massive 2 km/sec of deltaV in most configurations I end up with. It just feels s
Moving to Making History Discussion.
You appear not to have noticed the second connector node underneath.
My impression is that it's a hyper-specialized part that's meant to be a kerbalized version of the Apollo lander. With that in mind, it makes a bit more sense:
The built-in fuel supply is supposed to be for the ascent stage. It wants to to put some tiny little engine, like a Spark, on the upper connector node underneath-- not the one that activates the "collar", but the o