This has now been fixed as of the April 24th release of the program.  There is now a checkbox in the Individual module on Screen 3: Miscellaneous Info/Direct Deposit --> Massachusetts Miscellaneous that states "Spouse is physically or mentally incapable of taking care of himself or herself and principally lives with the Taxpayer."  Once this box is enabled the $310 credit will populate on the MA Form 1, Line 46.  Have a great day!