Solution : https://service.sap.com/sap/support/notes/1649901 (SAP Service marketplace login required)
Key words : 
aim mergepseudo-d-version reason, /saphelp_nw04s/helpdata/en/46/9199b2fa1a15ebe10000000a114a6b/frameset, processing step ain_newbas/xpras_aimmrg takes, time-critical processing, longer takes place, system processes execution, system processes rs_after_import_d, source system-dependent, -import method rs_after_import_d, error messages occur
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