I would do it like this:
macro pad_5
PUSH_META CLEAR_META all
SET_META ctrl
SET_META lshift
PRESS t
POP_META
POP_ALL_META
endmacro
Press sends both down and up, so it was releasing the state on the lshift before t was pressed. So it was pushing and holding the CTRL with the meta command, then pressing and releasing "shift", then pressing and releasing "t". My way uses the same "meta" command to hold down the lshift. I think you can remove the "POP_META" as well.
Another way to do this is with the "MAKE" & "BREAK" commands.
macro pad_5
PUSH_META CLEAR_META all
MAKE ctrl
MAKE lshift
PRESS t
BREAK lshift
BERAK ctrl
POP_ALL_META
endmacro
Pretty sure that will work too. I'm no expert on soarer programming, but it makes sense to me, Let us know if it works for you.
Note this is using the 1.12 (latest) documentation.