well ok. let's explain one thing at a time.
-First off, the campaign maps are stored in war3.mpq or war3x.mpq (depending on what map you are looking for). The mpq files are sort of like a .zip file, but windows can't open it on its own. Download "winMPQ" (do a google search for "winMPQ") and use it to open war3.mpq (again, this file is in your Warcraft III folder, probably in C:/Program Files.)
Now search for the campaign map you are looking for, and extract it where you would like. You can now open it and edit it as you please.
-As for your mouse cursor: All you have to do is set the player race to human under Scenario/Player Properties. Make sure you X the fix player start location box, and once done, click on the forces tab. Now you want to X the "Use Custom Forces" box. Forces are like teams, so set everyone on the teams you want them on, then X the "Fixed Player Settings" Box. Now everyone will have a human cursor, because they are the human race.
-For your gold mining problem: You will open your object editor. Now click the abilities tab. Go into the "Special" Folder. Inside that, Go to the "Units" Folder. Now scroll down and click on the "Harvest (Gold and Lumber)" ability. Now look for the line that says "Data - Gold Capacity" It should be set to 10. to mine 20 gold at a time, change that number to 20. **This won't work for night elf wisps and undead acolytes**
- Finally, to solve your saving problem. You need to know a little bit about triggers and how to use them. this trigger will save your hero and his inventory and level for the next map. The save will take place when the game ends.
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Events
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Player - Player 1 (Red) leaves game with a victory
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Player - Player 1 (Red) leaves game with a defeat
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Conditions
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Actions
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Game Cache - Create a Game Cache from MapName.w3v
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Game Cache - Store YourHero as Hero of Units in (last created game cache)
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Game Cache - Save (last created game cache)
that is just a simple trigger that saves your hero to the file named MapName.w3v (You can chage MapName; for instance to CoolCampaign.w3v, just make sure when you load you type the filename correctly). You can use this same file to keep a save file of your hero through your entire campaign.