If your Flex actor is interacting with Blast actors, then it’s working. The thing with Blast is, the parameters are quite sensitive. It’s been a while since I tinkered, but a previous project I worked on require A LOT of subtle tweaks and there to get things breaking as intended. And it’s different for each “type” of object, for example a thin stone slab versus a thick concrete wall.
I intended to do an article or tutorial of sorts covering these things, but I have yet to find all the “magic” numbers for parameters and further… Well, Blast objects are so variable in their setup, it’s hard to say to someone “check box and enter number in that field”. If someone else has some proven numbers, I’d love to see! Otherwise, it’s a process of tweaking, testing, tweaking, testing…