No, you can't. You have to do it in one run.
Also bugs: at the Eye of the Storm mission, go through the maps, but don't kill the bases. When you return, you get the mission rewards and it opens the last mission, The Invasion. You also get a lot of credits to upgrade your ship. Now go back to the Eye of the Storm maps, kill everything and get the artifact. You'll get the credits rewards again so you can buy more equipments again.
19, the same here. But the game runs better on my home PC, (17$ for the 1st day, not only 16) so it seems I'll be able to make it at home easily.
Since I had less money here each day, I bought the glider 3 from the 5k I got from the first run on the 35' ramp and skipped rocket 2. If I only could do a bit better, it could still be in 18 days as i missed the distance by 10-50 meters at least two times...
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