Need to perform bulk update for huge jira issues from different projects in instance

[Maha vishnu v]

We are in need to perform bulk updating more than 1 lakh issues in Jira from different projects ,
My Jira instances was integrated with replicon , Due to certain condition we need new fields to be updated in Jira issues  , So replicon team provided list of Jira issues more than 1 lakh count was provided in csv .
 
Resolution tried :
We were unable to perform system bulk update option because we were unable to preform the query
Import issue thru csv didn't help for custom field update .
We tried with script runner capabilities , It doesn't suit for my requirement .

Please provide alternate way to achieve this 
 
Community help needed !
 
Thanks ,
Vishnu .

[Nic Brough -Adaptavist-]

There are no "alternatives".  If you've failed to do bulk updates with CSV and Scriptrunner, then whatever else you try is going to be less functional and even more likely to fail.

I would look at fixing whatever you did wrong in your imports (or scripts_