Good News.
The latest beta build for my TRS19 version (104017 the non-plus version) seems to have fixed the problem of NavPoints not working correctly although they seem to have removed the display of the following NavPoint to be completed as a semi-transparent icon - if it is there then it has been rendered completely invisible. But it appears in full living colour and "solidity" when the current visible NavPoint point has been completed.
The latest beta build for my TRS19 version (104017 the non-plus version) seems to have fixed the problem of NavPoints not working correctly although they seem to have removed the display of the following NavPoint to be completed as a semi-transparent icon - if it is there then it has been rendered completely invisible. But it appears in full living colour and "solidity" when the current visible NavPoint point has been completed.