This was posted by another guy. I agree with it and added my comments below that. I post reviews successfully every time - so there must be some way to work-around the gremlins. :-) Here you go...

REVIEW ERROR MESSAGE WORK-AROUND:
I have found that if you start with the bare minimum it seems to work almost every time. And if it doesn't work you've only put in a short amount of time in case everything disappears.

I have posted this on a couple of different threads, but this is what works for me.
1. Fill in only required fields (the starred ones). Public comments is required, but I only enter one word.
2. Submit the review. If it is accepted then...
3. Click on "Edit your post" in lower right corner and enter the rest of the review.

My additional comment: Try "previewing" it instead of "submit". If the top part of the review doesn't look normal (usually a lot of spaces), check that the activities and physical descriptions sections are still there. If either disappeared, retype what's missing and try to "preview" again. If all looks normal, go ahead and submit. Then go to no. 3 above. Don't forget to use the "Hide" for the ROS. You can find this when you are editing by using the "Go Advanced".

Lastly, I recommend to type your review in a Word Document before you start the review. You can cut/paste it into the review and the information will not be lost if something goes wrong.

A'Man