@ Richard: According to https://help.libreoffice.org/Common/Using_Microsoft_Office_and , Calc and Excel use much the same language, but different objects and methods. It should be possible to migrate from one to the other once the correspondence is understood. I've done a fair bit of VB scripting. We can talk about this offline if you like. There's also the option to enable the feature Tools - Options' - Load/Save - VBA Properties'
But first you need to resolve this K-3 vs K-more-than-3 thing. My main interest at present is in the K3 version and people need to know what they've buying - one or the other or both. I gather that there may have been some initial confusion on this point.