In each textbox Interactive Change
and for some textboxes both in Interactive Change and in
Programmatic Change:
THIS.BackColor = IIF(EMPTY(THIS.Value),RGB(255,255,128),RGB(255,255,255))
THIS.Disabled BackColor = same as above

In my custom Form Init method SetBackColor:
LOCAL loRef, ii
loRef = THISFORM
FOR ii = 1 TO loRef.ControlCount
DO CASE
CASE loRef.Controls(ii).BaseClass = "Textbox"
loRef.Controls(ii).BackColor = ;
IIF(EMPTY(loRef.Controls(ii).Value),RGB(255,255,128),RGB(255,255,255))
loRef.Controls(ii).DisabledBackColor ;
IIF(EMPTY ... same as above))
ENDCASE
NEXT

I was thinking that if I put THIS.SetBackColor after the THISFORM.Refresh in my Next button code that might solve my problem. Instead of in front of Refresh as I tried before.