"Rotate/mirror effect produces the error "Encountered an improper argument", then this whole tab effects. What do I do?"
I've never seen this error. To help further, assuming bing is translating well enough, it would help to know which program and version you are using and exactly what object (clip or image file format) you are trying to rotate/mirror.
Also the translation to the phrase 'this whole tab' is confusing me. Do you mean an entire numbered track?
Я никогда не видел эту ошибку. Чтобы помочь дальше, если предположить, что Бинг перевод достаточно хорошо, это помогло бы знать, какие программы и версию вы используете и точно какой объект (клип или изображение формат файла) вы пытаетесь повернуть/зеркало.
Также перевод на фразу «this whole track» смущает меня. Вы значите весь номером дорожки?
Again, no problem here in any version of MEP I've had. Did miss out on MX and am now up to 2014 version 188.8.131.52. One suggestion is to download the free trial of the latest and see if that can do your effects as you want. If the problem persists, perhaps you have an odd clip that is behaving badly?
The 2014 trial works fine, tough I'm not really interested in paying another 100 EUR for a soft, which I use 1-2 times a year. I'm an amateour user, and use it only to process my personal recordings.
Today I also reinsatlled my MX version. In the clear installation effects work fine, but exporting movies fails. After installation updates, movies exprot is ok, but some effects (in particular - rotation) fail.
And it seems, that there has been no update for some longer time released. Is this version alreadey abandoned? I think it's yet too early to do so...
Only a user like you, so I've no idea how the folk at Magix decide on new releases. The usual pattern is a new version each year with one or more updates in between. I don't recall seeing an update for any version other than the current one. Unfortunate that the MX fix introduced a new bug.
One suggestion you might consider is picking up a cheap older version say on e-bay and have that available just for rotations. Awkward yes, but better than nothing. I just looked and there are listings for the newer MEP 2013 (standard not Plus or Premium) for as low as 16 EUR!