Customizing SlideShow.xml file in Confluence skin

[AMW]

I'm trying to customize the SlideShow.xml file in the Confluence skin to display photos' captions. I've been able to successfully do this running a version of XBMC on my laptop, so I know what changes I need to make. I'm having some trouble translating this over to a version of OpenELEC that I'm setting up. Based on my research so far, here's what I believe to be true:

• In OpenELEC, the SlideShow.xml file lives in /usr/share/xbmc/addons/skin/skin.confluence
  
• In OpenELEC, this part of the file system is read only, so I can't just SSH in and edit it
  
• It seems that to edit this file, people are suggesting making a copy of the skin.confluence folder in /storage/.xbmc/addons, editing the desired XML file, renaming the 720p folder to something else (like 720p_new), and editing addon.xml to point to the new renamed 720p_new folder
  
• It seems that upon reboot, OpenELEC should detect this new skin in /storage/.xbmc/addons and load it instead of the default skin
  
  I've tried all this, but my changes to SlideShow.xml aren't showing up. Any idea what I'm doing wrong here? I'm new to OpenELEC, but so close to getting it running just the way I need it. Thanks in advance for any help you can offer.
  

[AMW]

Update: After more digging, realized my error: I'm using a build of OpenELEC that's built on the newer Kodi. While there's still a xbmc folder on the drive, it doesn't appear to be used. I made the same changes but used .kodi in the folder name instead of .xbmc and all works well. (One add'l thing that I discovered: you have to select the new skin in the GUI under Settings | Appearances | Skins.)

[NilsHolgersson]

I tried to customize the SlideShow.xml file in the Confluence skin too, by using the method of user AMW, but had some difficulties:
I am not able to copy the renamed 720p_new folder back again and I am not able to change the addon.xml because all is read only.

Could someone explain me how to change the permissions of these files (mainly the SlideShow.xml) to be able to customise it?
Sorry, I have not so much practice in using Linux - normally I use Windows.
I am using Openelec on Rasperry Pi2. For SSH I use the FileZilla Client for Windows (7 x64). I tried to change the rights of the SlideShow.xml and of the whole /usr/share/kodi/addons/skin/skin.confluence - folder to 777 (using FileZilla) but all I get is "set attrs for /usr/share/kodi/addons/skin.confluence/720p/SlideShow.xml: failure".
Where si my mistake?

Thanks

[chewitt]

You cannot modify the embedded skins directly as they exist in a read-only filesystem - and this cannot be changed. Clone the skin files to /storage/.kodi/addons/ and edit the skin addon.xml to change the skin name, then reboot and select the renamed skin. You can now edit and fiddle with the skin as needed.

[NilsHolgersson]

Thanks for that hint. I will try it in the next days and give you feedback.

[chewitt]

No feedback required. This is the only way to do it on OE