Well the version of HRD that you are using was the last one released by the original author Simon Brown HB9DRV/G4ELI around the middle of 2011 so you must expect things to change over time and particularly the ADIF format which all logbooks use for data interchange - From memory back in 2011 the ADIF version was 2.04 and we are currently on 3.06 which is dramatically different.
Some software like NiMM logger do not even export the country name or DXCC number whereas Log4OM uses all ADIF fields for export and import.
I used to have an Icom IC-751 but my current IC-7600 is far different and vastly more efficient - Time passes and products including software get improved!
I am surprised that you find Log4OM a steeper learning curve than HRD because it is designed to be simple to use and our users generally confirm that - Perhaps its a case of your long term relation ship with HRD plus the advancing years causing this comparison?Both have their good points. LOG4OM, because i'm one of the older generation, has a learning curve that appears steeper than what HRD did years back when i first incorporated it into my logging process.
BTW I am 77 years old and actively involved in the development of Log4OM as I was in the development of HRD until 2011
Look on the bright side and your PROBLEMS with Log4OM may just become challenges! at least Log4OM is free and you also have totally free support on this forum, by email, PM, Skype, Teamviewer and in some extreme cases by telephone - Where else do you get all that for freeNow on to the next problem in LOG4OM.