can't switch between added subs

[Muis]

Hi,

I've just replaced the subs on a (already backupped) dvd with 4 dutch subs of different sizes.
but when i play it with powerdvd, i can't switch between them.
when i select a substream, it places a marker next to it but still shows the first one (the small one).

i did this :

-demux with decrypter
-subs SRT -> STL with sub2stl (created 4 different sizes)
-author in meastro
-added the new (measto) movie files to the rest of the original
-ifoupdate


thanks!