The back test will tell you a lot about you need to know. A forward test on a demo account will tell you more. And of course a small live test will be the truth.
Ah, now I understand what you're saying about the smaller ranges, but keep in mind that if you open orders at every 10 pips instead of 20 per the recommended settings, then you have to almost double your account equity to trade safely.
As a result, no, you're not within a safe range to trade - in fact you're nearly double the recommended risk. However, that's just that - recommended. Depending on your risk aversion or acceptance, you could say "Hey, we're pretty close to the historical high right now, so it's a great time to start with a high risk setting" and you could potentially make some very good money. However, if the market doesn't do exactly what you want it to do, and does something unexpected like move higher, then you either have to add a lot more equity (and fast), close a number of orders at a loss, or risk a margin call.
Bottom line - I don't advise anyone to trade more than what is recommended in the manual for the robot. The settings you choose to trade at should be based on your research (forward demo and live account testing) and your appetite for risk (or lack thereof).
WIth that said ... I am trading 0.1 lots on a 200:1 demo account on two charts with a 20 pip shift so I am essentially doing what you are doing, but I am doing it with a $5k balance. I was nearly margin called last week, and if things keep moving up (AUDNZD) I am sure to get wiped out. So my little experiment has shown me that these settings are VERY risky. If I had done the same with 0.01 lots I would have been fine. Even if I had been at 0.05 lots I would have been fine.
So ... do your homework and make your decision carefully.
