Solution : https://service.sap.com/sap/support/notes/692752 (SAP Service marketplace login required)
Key words :
missing version info file --> <designroot folder>/versioninfomissing themeinfo, xml file --> <designroot folder>/config/themeinfo, /irj/servlet/prt/portal/prtroot/, terms styleeditor versioninfo themeinfo, xml designservice lafservice reason, lafservice \themes\portal\<designid>, lafservice\themes\portal, lafservice\themes\portal\<, irj\root\portalapps\, irj\root\portalapps \
Related Notes :
| 589013 | EP 6.0: Central Note for Themes and Theme Editor |