I think i've found some "bugs" or "annoying things"

my old file (6.1) for toolbar's button is no longer compatible, i had to add an icon (you've added one button) ok, not a bug )

with the same mirc.ini config file, i look some differences between the two mirc
check those pictures
mirc 6.2:

mirc 6.17:

you can see that under the "menu", on 6.17 i have a double border, and on 6.2, a single one.
and between the toolbar and the switchbar, i don't have any border

the switchbar, is not as cust0miz4ble as on the mirc version 6.17
on the old one, we could use height and width for the switchbar's buttons. and i have the result of the screenshot, the buttons are sized depend of the text.
on 6.2, i can only set size to "small" and i get those huge buttons which do not fit to the text inside

i think this was the last one, so,
good bye

As we only need to see your top portion of your mIRC and NOT your entire display....

This doesn't seem to be a bug but more of personal request to make mIRC look like it's old versions. ;/

i don't like the new one

no, i think you are just not used to it. i'm sure you soon won't mind the absence of this 1 px line between the toolbar and the switchbar anymore. or at least i hope so...

I miss that line too.

this will probably have to do with "better support of XP and classic themes"...

i also had some problem to dock my customize toolbar using the hos.dll with mIRC 6.2, but is a problem of the dll.
Anyway now i have integrated my toolbar with the mirc toolbar so i don't have to use dlls anymore