FreeOrion

Excellent addition, so much strategic potential!

Is there a maximum length? Does it check if other star lanes are crossed?

No, but conditions might be usable to select the starlane endpoints based on distance from the target system of the effect (which is the other endpoint). I say may because there are some limits to the condition system when nesting conditions or using them inside effects, which can lead to multiple possible interpretations for "Target" in the effect script (is it the target of the effect, or the potential "target" that the current condition is considering matching, or the possible matches for the subcondition within this condition, etc...)


No, but I'm planning to add a condition to check if a starlane between systems would be geometrically acceptable, meaning it wouldn't cross any other lanes, pass too close to another system, or be too close in angle to an existing lane.

Is there a possibility that a part of the Galaxy gets cut of or separated from the other part (no starlanes connecting some regions). This would be a good strategy to clear a region, but also an exploit in my consideration. Is there a condition preventing that?

There are no built in restrictions to how starlanes can be added or removed using the new effects. Actually being able to do this as a player is would require some content, like a building or ship part, that uses the effect. That content, which is not editable by players, could have a condition that limits its use in whatever way is deemed necessary.

I wouldn't say it's an exploit. All it does is forcing the other player(s) to develop or obtain the same or a similar technology (like stargates for example).

Eleazar wrote some stuff about Precursor involvment. Adding starlanes could be a good way to allow a hidden system to appear (especially if the system had a lot of stealth) in a scriped manner in a campaign. Then all the problems about where the lane could appear would be solved (in this case only obviously).

Adding and removing starlanes is more complicated than it might seem. Adding a lane needs to ensure that the new lane won't cross an existing lane, or get too close to another system that it doesn't connect to. Knowing when this can and can't be done using effects and conditions (as opposed to a human looking at a picture) is very complicated. Trying to do this for a scripted event could be a problem if something else created a lane across the path you wanted your new lane to go, or if systems moved or were destroyed that you were expecting lanes to connect to. Using stealth avoids some of those issues by having the lane always be there, but just hidden.