How to re-render to a file with exact results

Hi, I want Reaper to be able to render my project to a file with exact results every time I repeat the process and to be faithful to what I hear in the project . I know some vsts have humanization, round robin etc which make some parameters of the sound random. Randomness is OK with me as long as it appears in a track the same way when the project is reloaded and replayed. I tried to set "inform plugins of offline rendering state.", but I have just rendered a project and got a part of few seconds different from what is played in the project. I actually rendered it again and that problematic part was rendered OK, which means, at the moment, I cannot trust the rendered file to be exactly as a re-rendered file or exact as the project. This causes me a lot of work and time wasted. Is there another option to set in Reaper in order to achieve this goal?

Whether randomization from plugins is repeatable will depend on the plugins themselves, Reaper can't do much, if anything, about that. I would assume most plugins with randomness just keep on generating new random values each time the playback is started, so it won't be possible to recreate the same sequence of random numbers. What are you exactly trying to do? Why do you need to be able render multiple times with the same results?

Any software instruments in particular that are giving you problems?

Have you tried freezing your software instrument tracks?

My suggestion us to render the midi instrument to audio so that the "performance" will always be the same. I never keep vsti's "live " in my project, they always get rendered to audio very early in the mix phase of my work. This allows me to make decisions and move forward, so it is like working almost with tape. For instance, when I use a drum vsti (Addictive Drums 99% of the time), after I am settled on the part, I render everything from that to audio files (all separate, in fact), so while mixing, it is exactly like working with actual tracked drums. So be default, this way of working will automatically eliminate the problems that you describe.

BTW, In regard to what I wrote, I rendered the mix as well as each individual track. The problem prevails in both mix and that specific individual track. I rendered these in parallel. Do you also rendered the individual tracks in parallel ?

But regarding "reliability", I have never had a problem with how Reaper renders my tracks.

David: "This causes me a lot of work and time wasted." No, it was you who caused you to waste time. Besides, how much time wasted in clicking a few settings and hitting render button again? A minute? Two? I will admit, there are some few things that are not extremely, totally well-explained in the REAPER guide, but the RENDERING function and its many options are not one of them. It's about one page I think. Check the table of contents and click on it. Some workstations offer many less choices and options on render. I know it takes a bit of clicking about in REAPER's render settings dialog box, but I like having every freakin' choice. Don't you?