7.1.5 to 7.2 upgrade fails

When upgrading from 7.1.5 to the 7.2 release, I get the following error messages:

Notice: Undefined index: EMIsAdminEquiv in /var/www/sugarneu/modules/Administration/DisplayWarnings.php(165) : eval()'d code on line 13
Notice: Undefined index: AM_ProjectHolidays in /var/www/sugarneu/include/SubPanel/SubPanelDefinitions.php on line 495
Notice: Undefined index: in /var/www/sugarneu/include/SubPanel/SubPanelDefinitions.php on line 499
Warning: include_once(/var/www/sugarneu): failed to open stream: No such file or directory in /var/www/sugarneu/include/SubPanel/SubPanelDefinitions.php on line 499
Warning: include_once(): Failed opening '' for inclusion include_path='/var/www/sugarneu:/var/www/sugarneu/include/HTMLPurifier/standalone:/var/www/sugarneu/include/..:.:/usr/share/php:/usr/share/pear:modules/AOD_Index/Lib') in /var/www/sugarneu/include/SubPanel/SubPanelDefinitions.php on line 499
Fatal error: Class name must be a valid object or a string in /var/www/sugarneu/include/SubPanel/SubPanelDefinitions.php on line 500

I’ve tried it on a mirror so the production is still fine on 7.1.5. I’ve tried it multiple times, the errors are reproducable.
Any idea what I can do to repair the 7.1.5 so it can be upgraded to 7.2 (which I like!)?

Thanks,
Ralf.

I should add that the following installation path was taken:

Upgrade from SugarCE 6.5.20 to SuiteCRM 7.1.4
Upgrade from SuiteCRM 7.14 to 7.1.5 when it became available

Then I tried the upgrade to 7.2 which failed.