>I have set up a DVD... I made an Blu-Ray ISO file
I am confused... which is it, DVD or BluRay?
I know that a DVD project will allow you to add computer files in the ROM content box... does BluRay have the same option?
I am making a Blu-Ray Disc, not a DVD, sorry.
What do your transcoding settings look like?
If you go to File > Project Settings > then click on the "Default Transcoding Settings" button. What is your maximum audio/video bit rate setting set too?
Just for troubleshooting sake, can you change it to a lower setting to see if the size of the ISO decreases in size?
I just did what you said it the" Maximum Audio/Video Bit Rate" setting is set to 15. That is the lowest setting.
The default transcode setting would only effect motion menus and the like. You can set timeline asset transcodes above that limit. It is a very tempting alternative, but I do not believe it is the source of the "content is really bigger than Encore predicts."