Hi Basis,
You have to include the SAPUI as a add-on while generating the stack for the SAP System.
With the new version of SAP Netweaver , SAPUI component is already available in the system and in that case you dont have to include the SAPUI 750 as a addon component.
Kindly let me know the version of sap netweaver.
To generate the stack for 750 SAP netweaver , you have to do it from maintenance planner available in SMP.
With Regards
Ashutosh Chaturvedi