Hello Piotr,
I have not experience in terms of STO‘s so I cannot recommend a platform or solution but since your looking for capital I cannot help than to
ask myself what would be the benefit of an STO vs regular shares? Since most people in the crypto market won’t even differentiate between ICO‘s and STO‘s, and ICO‘s are burned by scams and regulators, this seems to be a tough way to raise capital I reckon. Sorry that my reply will probably not be a big help. Did you try to reach out to some of our heavy hitters like @theycallmedan for instance or @themarkymark?
Cheers!