p.1 #2 · Using SB-900 on Mola demi with Flashpoint Bowens strobe bracket
The mola lumi bracket range was recently revised.
Initially only the lumi 1 was available. The lumi 2 was created for those who use the PW flex or similar and mount the flash on the trigger. The lumi 1 is without this and doesn't have the height. The lumi 3 is really just for smaller strobes like the Eli quadra, q flashes etc.
As the weight of the Demi will be on the bracket (it doesn't have an integrated handle like the other mola range) I doubt cheaper third party brackets would mount well. If they did, there probably would be some tilt creep with the Demi.s weight.
A height adjustable bracket such as a lastolite one would make for a weaker bracket hence mola didn't make it in this manner.
So either get the mola bracket which was designed for the mola or take a risk with a 3rd party bracket and hope it works for you.
-- also worth noting that the mola lumi also includes a new central deflector specifically made for speed lights (lumilux diffuser) that will help your speed light get close as possible to that signature mola output vs with a higher powered strobe.