update to hikashop business 2.6.2

I have a problem after a restore executed with akeeba backup. I reinstalled hikashop business 2.6.1 and installed the Nonumber tooltip extension, which i used on the /product/img_title page. The tooltip works, everything seems ok except that no custom fields are visible on the product page (they are showing and are editable in the back-end). I tried to fix it by upgrading to 2.6.2 (several attempts, with backend upload from joomla and ftp-upload to /tmp). the upload starts but fails with a blank page (just an * showing). On the update page there are several warnings: you reached the maximum number of downloads for this version; "invalid extension update".
Another issue is that I cannot remove some installation files from a previous install attempt with filezilla, obviously the permission is denied, although filezilla gives no warning, and I tried to set the permissions to 777 several times (see screenshots). I could rename the files but not remove them.
I would like to be able to update again, and then see if the display problem is also fixed. (our site is still in a development phase, not all menu-items are visible to everyone). There is public access now to www.oudmanschoenen.nl/index.php/webwinkel . This is a category-list .Clicking on a shoe shows the product page without custom fields, although they are not set to be hidden anywhere.
I already followed the advice given in post #235285 etc.without result.

I repeated the installation of the 2.6.2 from a subdirectory undet /tmp and now it succeeded.
Also the custom product fields show again on the product page, so there must be some relation.
I'm glad everything works now as it should.