I'm playing through the first Sacred game as a Wood Elf. I recently started picing up spells like Plant Cage and Transformation, but they don't seem to work. Casting Transformation causes a green circle to appear on the ground, but nothing seems to happen to enemies, even if they touch the circle. As for Plant Cage, it doesn't metter how much I mash the right mouse button, it just does not seem to cast the majority of the time. Maybe 1 out of 10 presses the spell will actually work.

I've gone through the manual but I can not figure out what I'm doing wrong. The spells have certainly cooled down so I *should* be able to use them, but for the most part nothing happens. Any ideas?

Most probably your spells levels are too low and level of enemies is too high for those spells to work. If you want to get those spells online, you have to use more runes to raise their level.