Hi Guys, need some advice to change the logo in my site.
I have tried using Site settings / Appearance as the tutorials inidicate to use but No matter what I do I cannot make my custom logo apear in the drop down list to select as new .

•  I have tried to upload a new logo in site settings but although I have a browse button which picks up the name of my logo there is no finish the upload button ( is it supposed to automatically load it to site root),
• I have also selected my new logo and then clicked the update settings button but no luck.
• I have also manually copied  the logo into site root images and the various folders there, 
• Copied it into  portals_0 root along side the awesome cylcles logo and logo.png which were already there ,
• Copied it into portals_0 /  images alongside awsome cycles logo and banner1,2, 3. team_chris and team_will images etc. (and this is really odd because when I go the images folder in site settings,  I can see those  images but mine is never listed). 

Can someone tell me what I am doing wrong? and importantly which folder should I import logos ,banners for the whole site into