I think this was released for Europe a long time ago as Jewel Master: Cradle of Rome. I actually played all the way through it, there's 100 levels in all, and the ending's pretty disappointing besides the accomplishment of doing it (I was hoping for vestal virgins or something.)
Anyways, the two big tips to plow through this game I didn't really figure out until level 60 or so:
- The special items help differently on different levels. Sometimes the Lightning Bolt isn't the best item to use, sometime's it's actually the Bomb or Shield.
- I'm not sure how to hide a spoiler so... SPOILERS BELOW
If you know you're not going to make it through the level, or want to start with a different special item, just hit Start and Restart the level. There's no penalty and it cycles randomly through the special items. Note that you do NOT keep the resources (food/money/building materials, etc) you've won for that level if you lose or restart the level.
I know, these 'tips' are probably pretty lame and obvious but like I said, I didn't bother noticing either until later in the game. *shrugs*