Over the course of time spanning the last time HullBreach Online was restored to the present, I have been focused on finding a way to complete missions. As players will come to know, doing missions normally does not grant any reward as it should. The thread "Regarding game problems" documented a technique to complete missions along with other miscellania. I have since revised that technique, to the point it is easier and more accurate. Therefore discussion of the specific topic of mission completion will continue here.
Note, the following information pertains almost exclusively to use of HB Online Lite on the DSi browser. Also, the term "planet" is used to describe any endpoint location for a mission.
The original method involved quick tapping the refresh/stop button in the hopes of stopping the auto-reload which eliminated obtaining earned credits. Eventually deemed too arbitrary.
Considerable improvement on said method involves a means mentioned before. It does still make use of the refresh button. Once a mission is selected, depart for the destination. After entering the destination's sector, select the correct location. Now go to the refresh button and hold the stylus depressed there. Carefully watch the main screen for the planet as your ship approaches. Release stylus once the back end of your ship passes the edge of the planet. Releasing before the ship meets the planet or while a portion still is outside the edge results in nothing happening, so you can reset location and try again. Releasing when the ship is square to the planet's centre means you are too late, and your mission has been dispelled. I found the success rate to be much improved even after only a few attempts, but sharp reactionary timing is still required.
Distance could vary slightly due to the size of your particular craft's sprite. In this way, it is best to use the ship's centrepoint as your reference.
The script's reloading effect seems to occur also after the fact. Following success and the "Mission completed" confirmation message often is another reload. While the loading bar is active: failure is a white screen (page never fully loaded), and success is that brief message that does get dispelled when refreshed. What influences the secondary spike, I don't know, but it does not affect the mission at all.
At this point, my go-to strategy for completing missions has changed. It is also mindnumbingly pedestrian. I simply hook up to my weakest, slowest internet access point. The maximum delay allows for the credit addition to trump the second reload, rendering it ineffective. And all is as intended.