I managed to run a few tests and it works!

In T49234#791232, @Kévin Dietrich (kevindietrich) wrote:

You have to apply the patch and compile Blender to test the feature, it is not in the daily builds. Also your file does not have velocity information (the array size is 0). So without the patch and without custom velocities, Cycles is just using an interpolation between the previous, current, and next frames.

I have some blurriness, but it doesn't seem to look right. (see Images)
This is a particle system that I exported and then reimported to reverse the movement. And the plane is a dupliobject on the vertices of the ABC.
I would not expect to see a clear outline of the plane in the image with motion blur. Also, the position of the blur is set to Center. But this seems more like Start. And the shutter duration also has no effect.

Maybe this is worth adding/fixing:

removed... @Philipp Oeser (lichtwerk) was quicker. :)

Hm... now I'm not sure. I'll just post these pictures and let Devs decide if this could be related.
My scene has Volumes in there, but I disabled them to pinpoint the problem. DoF or Volumes don't seem to make a difference for this.

@Antonio Vazquez (antoniov) Ah good to know. 2.81 FTW! ;) Thank you!

Ah, thank you for creating the task! :)

In T57818#556355, @Antonio Vazquez (antoniov) wrote:

If you want to paint a weight (0.5 for eg) onto an existing stroke, as far as I can see this isn't possible currently.

Done in ec908beab321

Can confirm. The daily build from last night also crashes on my system.

Ok... thanks for the info. It seems unrelated.

How much of your GPU memory is used? I'm asking because I might have a similar issue.
For me, this occurs, when GPU memory is close to full. Then, some geometry seems to be omitted from the GPU, resulting in a tiled look. I'm using Microdisplacement btw.

Possibly related to: T66125 ?

In T66125#707324, @Sybren A. Stüvel (sybren) wrote:

What happens if you give it some time? Does it time out after a while?

In T66125#706981, @Sybren A. Stüvel (sybren) wrote:

Please don't report two bugs in two add-ons in one report. They are related but developed & distributed separately, and those two issues have not much in common.

Of course. It seemed like one issue/possibly related to me.

The "assign as a type annotation" is only reasonable, because the add-on targets the latest release of Blender. Of course we try to keep it up to date with 2.80, but fixing those warnings would break compatibility with 2.79. If I'm wrong about this, and there is a way to fix them and keep 2.79-compatible, let me know.

Thanks you for the explanation. That helps to understand the warnings. The only thing I can think of right now would be to suppress them if it is 2.8x. But it's hard to judge for me if that could have other implications.

The login validation of Blender ID should be reasonably fast, but depends on the speed of your connection to the Blender ID server. @Michael Hermann (245) how responsive is https://id.blender.org/ for you?

It's as responsive as any other website. No noticeable delay whatsoever.

In T66125#706844, @Craig Dolphin (craigdolphin) wrote:

I just downloaded Blender Cloud addon and it was version 1.13.5, not 1.9.999. It didn't generate any errors on Win64 on the 6/22/2019 build of 2.80 FWIW.
I'd suggest going to https://cloud.blender.org/services and re-downloading the addon and trying again.

Was about to report this as well. I can't get anything to show up.

I ran into this as well.
"Space" only moved a few vertices around when I had the whole mesh selected. But no discernible logic behind the action.

@Antonio Vazquez (antoniov) Thank you for checking it out again! :)

I am still seeing the same results in Cycles. In my file, as well as in your testfile, @Antonio Vazquez (antoniov)
I tried with the build from last night.

Can confirm!

Looks pretty nice, @William Reynish (billreynish) ! However, I'd prefer the filename and path both at the top. As well as the buttons. On large and high-res screens this is very far apart. Even with the current layout, the "Open" or "Cancel" etc. buttons are already far to the right.

In T63263#654844, @Ray molenkamp (LazyDodo) wrote:

[...] other hand you can easily navigate to any part including the parent folder of the path by clicking on it.

In T63276#654714, @Marco (nacioss) wrote:

Can't reproduce the crash in Ubuntu 18.04.2 with AMD RX580

I bet many are using ".." a lot to click on it as well. I (personally) would really like to keep it.

@Stephen Swaney (stiv) :

I'm willing to argue that going to the parent directory takes precedence.

When I box select e.g. 5 materials and accidentally ".." the I would definitely like to append the materials, rather than go to parent dir.

This might be helpful: https://blender.stackexchange.com/questions/134545/extreme-motion-blur-for-particle-bullet-tracers - See my answer there. I tested the original file.
TL;DR: Camera Shake seems to be the cause.

@Antonio Vazquez (antoniov) Seems to work as expected with Eevee. No issues.