According to information on the LCModel website, as well as creating the ~/.lcmodel/license file you must also supply the master license key in each control file (adding a line: key = 210387309).
The latest publicly-released version of MRspa is from August 2018, which predates LCModel’s switch to free licensing – so it won’t handle this for you directly. However, look at section 4.5 for the MRspa manual: you should be able to edit the control file template used by MRspa, to add this line:
key = 210387309
Otherwise, if you are comfortable building LCModel from source (using the instructions here), it is also possible to disable the license check completely (but modifying your control files will probably be easier). Around line 2532 of LCModel.f :