I have successfully imported the following files: .STEP / .stp / .ipt / .sat / .iam but neither of the two you mentioned. Upload the file from the Data Panel. After upload, it should show up as a thumbnail, right click on it & then 'open'. Parametric mode will be disabled but there's a workaround on youtube (https://youtu.be/H-N1LZufT_o). Good luck.