-When you acquire a skill book (for example: Banish, Freeze, Poison Cloud, Hell Spikes, etc.) keep it in your inventory (spells and scrolls). Save the game before you start to duplicate it. After the game is saved, drop the skill book that you want to level-up from your inventory, then save this as a test saved game. Go to your save game folder (that you saved before dropping the skill book) and copy all six INV items and paste them into your test saved game. When you reload you test saved game, your old saved game inventory will be in your test saved game and that your skill book will still be on the ground. Repeat this until you have a total of five or more skill books. After that, click on the skill books (five times for the maximum level 5 ) in your inventory to learn it as usual.
-To get more skills, experience and statistics, complete a quest and save before you before you speak to the person that gave you the quest. Talk to that person, get the bonuses, then make a new saved game. Quit and go to your "savegames" folder. Go to your first saved game (created before you informed the person that gave you the quest). Copy everything inside it except the "data.000" file and paste it on the second saved game (after you informed the person that gave you the quest to get the bonuses). To get more bonuses, spare your first saved game and repeat the process. This also works at the Wishing Well.