Hello & welcome, @pestrickland to the forum and the software.
Thank you very much for the feedback and the error messages which I’m sure will help tracing the bug. I’m on Windows 10, so I really can’t help you, but @slspencer, @Pneumarian or @Douglas will get back to you soon.
In the meantime, have you tried double clicking on the pattern file from the explorer? I don’t even know if one can do this from Linux. 
@pestrickland - Please tell us which distro do you have (Ubuntu, Manjaro, ?). And which version release of the distro do you have? Or if it’s an Arch- or Gentoo-based distro what’s the date of distribution?
It’s a problem with the desktop and theme:
If you have Ubuntu, try this:
sudo apt update sudo apt upgrade
sudo add-apt-repository ppa:papirus/papirus sudo apt install papirus-icon-theme
This is a workaround for now.
The longterm solution is to include the icons in the AppImage.
Optional: If you want to set Papirus to be your desktop icon theme:
sudo apt install gnome-tweaks -y tweaks
Select Appearance, then select Papirus as your Icons theme.
This may not be necessary, maybe all you need are the Papirus icons installed on your system as described above so the AppImage can find them.
Another approach: What happens if you launch Seamly2D with AppImageLauncher?
$ sudo add-apt-repository ppa:appimagelauncher-team/stable
$ sudo apt-get update
$ sudo apt-get install appimagelauncher
From kde - Registering AppImage Files as a desktop app - Ask Ubuntu
Hi, I’m using Manjaro with Gnome 40.0.0. However, I got the same behaviour running in Mint with the Mate desktop. I already use AppImageLauncher, but I will give the Papirus work around a try.
Thanks for your quick work on this!
OK so both your Manjaro & Mint installations have Gnome-based desktops. Not that this is the final answer, but the missing Papirus icon message was a surprise so I’m looking into it first.
I’ve tested the latest appimage on Ubuntu 20.04. SeamlyMe doesn’t crash when clicking Open so it is finding the papirus icons but it can’t find the diagrams.
I got lost down the grant writing rabbithole. I’ll pick this problem up again ASAP.
I just loaded the latest appimage from the github repository and the only issue I noticed immediately is that the main window can not be repositioned on the desktop and it does not have the tiny square at the top right of the window that would allow switch between full screen and resizable. It does not appear as full screen so will limit the working area available.
Well that’s interesting. Have you tried grabbing the lower right corner and dragging the size of the app window?
Let me ask… is this something that is just showing up now with the latest Linux build?
Unless this a Linux specific issue, not sure why the window min / max button would disappear… it’s on the Windows ver I just built, and it takes some specific code to add or remove the button - which I’m sure hasn’t changed.
I"ll try and take a look at the Linux build on my one laptop, and see what’s up.
Odd. I don’t know how my settings may differ, (I’m sure they do,) but I’m also using Ubuntu 20.04.3 & have the resizing thing, & it’s full screen.
Just loaded the 8_30 weekly build AppImage… and it filled my screen vertically, but left space horizontally to the right. Mine has the min / max “square” button.
Mind you I have used Ubuntu all of about 1/2 dozens times… but I figured out if you right mouse click on the Seamly2D pattern file in the tray a context menu pops up with Min, Max, Move and Resize options. I was able to resize the Seamly2D to full size. Closing and reopening the app is sized at the full size. I’m assuming this is due to the saving of the Window size and position in the Seamly2D settings INI file.
BTW… another “resizing” issue I think I have fixed in the Dialog overhaul update I still need to push… is the elided text in the Toolbox tool buttons - which Ubuntu handles a bit different than windows with the “tab” look to the button -which cuts off about a 1/3 of the text. Currently the “toolbox” itself doesn’t resize when resizing the dock.
Well that’s interesting. Have you tried grabbing the lower right corner and dragging the size of the app window?
I had not, and when I just did it had no effect. I also tried a right click at the top of the window and got a (ubuntu specific?) menu that allowed me to move or resize the window.
Let me ask… is this something that is just showing up now with the latest Linux build?
I can’t say whether this just showed up because I this is my first ever attempt run any appimage version. I had a much older version from before you were doing the appimage and that one worked as expected.
You can see from my first screenshot that the little square box is not there. It is as you mentioned below the vertical space is filled. using the ubuntu menu I was able to stretch seamly2d fill the horizontal space.
This does not rise to the level of a problem, it is more a curiosity.
Odd. I don’t know how my settings may differ, (I’m sure they do,) but I’m also using Ubuntu 20.04.3 & have the resizing thing, & it’s full screen.
I have no idea if our settings differ. From my screenshot above, I hope you can see that I am using Ubuntu 20.04.03 and the Gnome desktop 3.36.8 under the X11 windowing system.
Indeed. I can understand the sizing of the Window changing as installing a new version of the app with new features can reset the app settings, but the sizing button disappearing for you baffles me - at this time.
I’ll try and keep an eye on it and see if it in fact an issue.
Hmmm… looks like it might be a good idea to pick up a few more USB sticks so I can run different flavors of Linux. 
