Do US PS1 Games downloaded from Playstation Network work on a PAL PS3 Console

Portugal is a PAL region. The UK is also a PAL region. There should be no problem. If you happen to have a game not from a PAL region, here is a compatibility guide.

PS3 games are region free but the game saves are apparently not. I haven't used any cross-region games on my PS3, so I haven't experienced the particulars.

Someone does suggest a (fairly complex) method of getting around PS3 save region lock though:

(you need a pen drive, PSP or any other USB mass storage device)

1. On your old game/PS3, copy the save to the device. (select it, press TRIANGLE and choose Copy. Choose the device)
2. Go to a computer and plug the device in.
3. Go to My Computer>your device>
4. Open the PS3 folder and then open SAVEDATA.
5. Copy the folder to Desktop then delete it from device.
6. On your new game/PS3, start a new game and save.
7. Copy the NEW save to the device. (select it, press TRIANGLE and choose Copy. Choose the device)
8. Go to a computer and plug the device.
9. Open PS3 folder again and then open SAVEDATA.
10. Copy that folder to a new folder in desktop.
11. Now, rename the NEW folder so that it has the same name as the old folder.
12. Open the NEW folder. Here you should see these files:

PARAM.PFD PARAM.SFO PIC1.PNG ICON0.PNG SAVE.DAT

(if there are more files that's fine. Sometimes PIC1.PNG isn't there, that's fine too.)

13. Open the OLD folder. You should see the same items.
14. THIS IS IMPORTANT: MAKE SURE YOU DO NOT MESS UP. Copy PARAM.PFD and PARAM.SFO from the OLD folder to the NEW folder. If you do it the other way round you'll mess up.
15. Delete the saved file from the device. And also delete the OLD folder. Drag the remaining folder into PS3/SAVEDATA/.
16. Goto your PS3, select Saved Data Utility, choose your device and find the data. Copy this (TRIANGLE) then you're done. Delete save from device.

Play the game and enjoy. This worked for me -- it should work for you too.

This should work for any PS3 game, ME3 included if ME3 is indeed region locked; and since it's EA, I would go ahead and assume they did as much locking and DRM as feasible.