1. The reticles of are prograde and retrograde markers. The markers to indicate your forward velocity, and its opposite.
2. The progress bar will go ahead as you progress through the stages. Since this is still "Stage 1" the progress bar is on easy. As you move to stage 2 it will get harder slowly and steadily.
For Stage 1 it can't go past beyond "easy" difficulty.
Your review was very detailed and insightful. We are making detailed notes based on these and are planning to fix all the issues.
I'm glad you enjoyed the game! Look forward to more updates in the future!