@
jackie_w - FWIW - another way,
- install the 4.99 portable in c:\_calibre4.99\portable;
- install the 64 bit 4.99 beta in c:\_calibre4.99\64 bit;
- copy c:\_calibre4.99\64 bit\calibre to c:\_calibre4.99\portable\calibre;
- uninstall the 64 bit 4.99 beta in c:\_calibre4.99\64 bit.
NB: the
c:\_calibre4.99 locations are notional.
If/when a new beta is released repeat steps 2-4.
This will leave your 'everyday' calibre as is.
BR