ivanl

I think you may want to search for Symbols.

I just had this same problem but the solution above didn't work because my slices are embedded files. 
 
It turns out that the image's fractional positioning caused the problem. 
 
For example if your image (50x50px) is positioned in (y:100.6 x:50) the slice will be 51x51.
You won't be able to align the slice square onto your image. 
 
I don't know if this is a bug or my lack of knowledge. 
 
I'm not using strokes, so the alignment isn't a problem. 
 
 
I hope this helps anyone with this problem. 
 
 
Update: 
 
I encountered a problem with an image of size 83.5x83.5 
 
The slice size cannot have decimal points, I even changed it manually. 
 
Does anyone have any advice ? 
 
For now I'll try exporting this manually.

Thank you, sorry I don't now the correct terminology. 
 
The link that I posted was basically a file that shows an app icon in multiple sizes. 
You can edit an embedded file and it will be applied to all the various sized icons. 
 
The file also makes exporting all the various sizes simple. 
 
I wanted to learn more about how to set up a file like that. 
 
 
Thank you

ivanl, 
 
Embedding an SVG file as a document is mentioned in the Lace Frame Galleries 2 project.
In terms of templates, by looking at the link you added, might you be referring to our Symbols feature which was introduced in the Designer 1.5 release? This is also covered in the workbook in the Tix App 1 project.    
 
Regards
Andy Capstick

Hi,
 
In response to requests for a quick peek at the Table of Contents...
 
Hope it whets the appetite.
 
Regards
Andy Capstick 

ivanl,
 
Welcome to the Serif Affinity forums. :)
You are correct, 100% transparent objects cannot be selected with the move tool. This felt wrong to me particularly when it means that drag select and Cmd+A doesn't pick them up either.
I questioned this with the system architects and they confirmed that items that are not visible (check box in the layers panel) or 0% opaque (in the layers panel) will currently not select, though this wasn't fundamental, and was possible to change if a compelling reason was found. I couldn't think of one.
Although I think I agreed on the 'not visible' case, I was less convinced about the correct behaviour when transparent.
What is your opinion please?