Not bad considdering you're not a Photoshop Pro.
A few things you could improve though:
- shadow effects beyond writing on paper are a no-go.
- the font selection isn't very suitable, neither for GES nor for the scene theme
rather use typewriter fonts like courier, stamp fonts etc. and place the custom on the folder too.
- also be carefull with other effects on these fonts too.
- the MI6 Sign shouldn't be squezzed, rather scale it proportional and have it cut off by the bottom of the format.
- you missed to cut out the hole in the hammer, looks strange to have it white
- the bevel and shadow effect on the folders is incorrect, rather do every single folder as a seperate object.
- the bevel on the photos is much to strong, white border is to thin
- no need for the Logo
- keep in mind that there needs to be enough space for the hints
- also that there needs to be 16:9 and 4:3 version of the loadingscreen
And pencil isn't a good idea at all.
If there would be a writing instrument, it would be a biro, but there are allready enough elements in that screen.
The Human brain can only recognize and remember up to 7 things at once anyway, so better keep it at 6 visual elements max.
since the hint will be #7.
As for using Mangleys template, i'd say it's not exactly mandatory, since it's custom content a custom or modified loading screen wouldn't be the worst thing. Even casino has it's own loading sreen customisation.