Solution : https://service.sap.com/sap/support/notes/39321 (SAP Service marketplace login required)
Key words : 
maintain capital investment program positions, abap/4 runtime errors occur, receive error messages ap019, additional key words laipcu01, capital investment program, regular entry transactions, program saplaipc, program  position, edit screen, maintenance level 3
Related Notes : 
       
| 398983 | Information: IM (Investment Management) | 
| 80057 | IM: Program position creation -> ASSIGN_LENGTH_0 | 
| 48103 | IM: Error AP130/AP131 when deleting edit screen | 
| 48064 | Cap.invstmt progs:edit screen cannot be deleted | 
| 43723 | Unjustified AP019: length of entry is not correct | 
| 40357 | CIP: Error AP024 when creating edit mask | 
| 39311 | IM: Runtime error when maintaining edit screens | 
| 26393 | IM: Maintaining coding masks not possible OR ... |