Created attachment 144119 [details]
File to reproduce the loss of names on export
Open attached file and open the Navigator. Notice, that all shapes have custom names.
Export it to pptx.
Open the exported file and open the Navigator. Notice, that the shapes have got generic names.
Besides the loss of information it is a severe problem, that the shapes on different slides have got the same generic name. That makes it impossible to select a shape by double click in the Navigator. Try to select e.g. "CustomShape 2" from Slide 2 via Navigator.
PowerPoint is able to handle custom names of shapes. Therefore the names, which the user has chosen, should be used in export.
Confirmed on windows 7 x64 with Version: 18.104.22.168 (x64)
Build ID: 0c292870b25a325b5ed35f6b45599d2ea4458e77
CPU threads: 3; OS: Windows 6.1; UI render: default
Also reproduced in