This is based on stevethefiddle’s excellent FadePlus effect - https://forum.audacityteam.org/t/more-versatile-nyquist-fade-amplify-effect/14040/1
I took an axe to it 
and changed it to an expanded Fade In / Fade Out effect, removing much of the flexibility (and complexity) of the original. But for those users who just want to fade in or fade out but are not happy with the built-in effects (which are limited to a linear fade), this may be useful.
– Bill
FadeInOut.ny (4.82 KB)
I’ve only had time for a quick look, but I’m only getting Fade-ins and not Fade-outs.
What’s the motivation of this simplified version? Do you think the full version is too complicated?
Personally I find the ability to produce a partial fade (for example fade down to half volume) is one of the most useful features of full version.
I’m having doubts regarding built-in help screens for complex plug-ins;
My thoughts at the moment are to just include a help file that can be zipped up with the plug-in (until such time as support for help screens in Nyquist plug-ins is improved).
The main advantage from my point of view is that the development and release of useful plug-ins will not be unduly held up as refinements to the documentation can be done later if deemed necessary. For the user of the plug-in I think that this approach is only a minor inconvenience compared to the greater issue of being kicked out of the plug-in after displaying a help screen.
Oops 
Fixed now
Motivation? Get reading and programming Nyquist to get up to speed again. To possibly replace the current Fade In and Fade Out effects which only do linear fades. Possibly as a “Fade Plus Lite” for users who don’t want the complexity and just want to do standard fades to/from 0 from/to 100%. Possibly something I will use and will never be distributed.
Not having gone through that process, but having read recent threads where help screen issues took up most of the discussion, I’d agree with you. If there’s a plain text help file, the user can have that open alongside the plug-in, which is more useful than reading the help, then having to invoke the effect again and remember what you just read. If the help is in the effect then the user can’t lose it, I suppose. But a some point you just have to say RTFM.
– Bill
FadeInOut-02.ny (4.85 KB)
Yes that works.
The “partner” effect for this would be a simple plug-in to produce partial fades.
I wrote one some time ago, so I’ve dug it out, updated it and posted it here: https://forum.audacityteam.org/t/simple-plug-in-for-creating-partial-fades/16055/1