Sorry this is a late reply, Sunday night & you leave on Monday, I will keep it brief. What you are taking in clothes sounds fine to me, you will be OK.
1. Dress code on boat, no problem, just dress smart casual for evening meals, no jeans, shorts, vests. Men should ideally wear a pair of slacks, trousers, or chino's and a shirt (open neck is fine). Ladies wear what you like, other than shorts, you will always look nice whatever you wear.
2. During the day you wear what you like, swimwear on boat, shorts & vest if visiting the sites. (other than a mosque when you ladies should cover your bare arms etc.)
3. Do not tip until the end of your cruise, then at your discretion.
4. If your boat is all inclusive then all local beers & spirits are included and maybe your bottled water, so that will keep your costs down.
5. I would suggest that you don't go buying any of the other things like on board videos or photographs to conserve you money.
6. Remember that you may have to pay for extras with sterling and not local LE Egyptian pounds.
If you have one of the main credit cards take it with you it is acceptable in most ATM machines, Sterling cash is also readily converted.
7. Pound coins are OK for tipping when you first get there. Change a LE 50 or LE 100 note into smaller notes i.e. 10s 20s when you get on your boat or at the bank at the airport.
8. If you don't already have your visa, remember you will need a £10 note for each visa (person) you need to get at the airport upon arrival.
9. Finally if both parts of your holiday are fully all inclusive you should be OK. As you should only need money for odds & ends. But if you budget for not exceeding a spending per day of LE 280 between the two of you, you will be fine.
A meal for two = LE 100
A bottle of water = LE 5
A bottle of local beer = LE 20
An average taxi ride = LE 20
The entrance fee to an average tourist site = LE 25
The above are a very rough guide to give you some idea of costs per person. Sorry I have to be
Vague & brief, it is a pity you did not find this site sooner, we could have helped a lot more.
Anyway good luck and enjoy your holiday.
Tez