I’ve recently been plagued with 2 problems in editing the layout of my 
blogger template. First is I can seem to add more page elements because the “add page element” is missing as described at the Known Template Issues at Blogger Help. The second and more annoying one is that I can’t scroll all the way down because for some reason the lower part of the layout is missing. This is also described at Blogger Help. Check out the screen shot below.
If this happens to you, may I suggest you check out 
blogger Help first. If you’ve tried their solution and can’t resolve this issue, try my solutions below:
1. The simplest way: On the page elements page, click on edit html then without editing or doing anything click on the save template button. Click on Page elements again and voila the “add page elements” is back and now you can also scroll down the bottom. Very easy!
2. If the problem persists, go back to edit html, tick the expand widgets radio button and check for java scripts. Delete them. Also delete those that start with 
.
DO NOT REMOVE ANYTHING THAT RESEMBLES 
as this may mess up your template. Save it. Then look at the front end of your website. If there’s been a significant change on the front that you don’t like, put the code back. I’d suggest that if you’re going to delete a few things, start at the bottom of the HTML codes. This lessens the possibility of committing a huge mistake that may severely affect the overall appearance of the front end.
4. If these don’t work, go back to number 1! It always works for me. Although it is not a permanent fix, I rather do this every time than not doing anything at all. 
There’s actually quiet a few issues with blogger and these are the fixes I found to work for me.
I hope this helps. Cheers!
