The first time a breakpoint in an LO macro is hit the code doesn't break. Run the macro again and it works OK. For instance:

Sub Main

dim i as integer

i=1

While i < 5

' Put a breakpoint on the next statement
msgbox ("Repeat " & i)
i=i+1

wend

msgbox (" ended")

End Sub


1) Save the macro within the document (it doesn't seem to matter if it's a Writer or Calc - I've not tried others). 

2) Put a breakpoint where indicated.

3) Run the macro from the Tools|Macros|Run macro menu (note: you have to do this from the main LO window, not the LO Basic editor window - no idea why!)

4) It runs to completion.

5) Repeat step 3

6) The breakpoint works.