I think that in part,  the reason Dick Karl finds getting up to speed in the Lear as opposed to his Cheyenne.  Is mostly because it is your aeroplane which you are very much a part of.   When a FO in a two crew operation, there is the niggling check-itis munching away and knowing that you can fly a turbo prop, tend to feel there is higher expectation for you to be up to speed  The older we get the slower we learn to change and from what I read, you tend to still be in Cheyenne Mode when in the Lear   (A sign taped to a glear shild on a larger jet, read).  You are the co-pilot, you're here to help fly this aeroplane.   The FMS is a gem of a tool and has its mystries to many who have never sat down to study its logical ways of moving metal through the air.  See it as a Computer first.  A Computer with with 6L and 6R buttons that retrieve and enter data.  The nuro alpha keypad is a bit different to a standard keyboard, but its an aircraft data key baord with an Airoplane programe in it   A book by Stephen M. Casner released through ASA, which might help you is titled. The Modern Airline Cockpit   Coves the main workings of the FMS in a way that the mistery is removed   As the Lear likes to move along at 7 mines a minute, that means you have to think at 9 minles or more a minute.  Brain is seeing it is in the air and moving along a bit faster than in the Chyenne and has a few more gadgets to play with as well as, talk about what is happening  Thinsg it doesn't do in the Cheyenne  So Dick, tell it that its to work in Lear Mode.   Hoped this has helped you.