Same thing happened to me a couple of months ago, also on Linux. I contacted support, but then managed to fix it before Ralf could respond.

My log says I fixed it by using zipfix.

And for the record, and in case someone searches for this in the future, the message I got from the command-line zip utility (the GUI tools weren't as specific) was:

I just bought the 2022 annual and decided to try an Ice Cavern.

When I got to the point where I wanted to draw elevation changes, I went back to watch Ralf's live mapping session. But... I'd added a few effects that were conflicting with Ralf's technique in other places, and I must say I'm not a fan of creating tons of sheets.

But some creative spark ignited and I came up with an alternative. The result is very subtle (because the lack of bevel makes each "step" less pronounced) but I like it a lot. And I can add many many steps without having as many sheets:

I created a single FLOORS STEP sheet and drew lines with a solid 10 Bitmap (if you hadn't caught it, you might look at the image above and realize it's there... just a faint shade in the top part of each step).

And then just a Wall Shadow, Directional effect, and an Edge Fade, Inner afterwards..

Just for completeness, I tried setting the line to 0-width (the two rightmost in the following image), but the result is even less noticeable (though it might be what you're aiming for):

Of course, given the Sun Direction in my directional wall shadow, these steps only seem logical if going downwards or leftwards, but you can create a new sheet. Two is still a small number. :)

One final note: I had to snap the steps to the nearest point in the cave wall, otherwise I'd get transparency acne (not an issue on the 0-width line).

I'll throw my $0.02...

It helps to see layers as "labels". Even with al the tech stuff aside, it helps organize your work. A fountain and a building might be in the same sheet (SYMBOLS*) but they're a different thing, layers come in handy here.

But organizing your entities is just the first step. You can have many walls in the WALLS sheet but a few of them are on the SECRET layer (allowing you to hide them on the player handout).

Remember that when selecting entities, CC3+ allows you to pick by layer. So you could, for example, freeze everything but the ROADS layer so that you don't accidentally modify rivers, or terrain/vegetation fills. Or maybe you can select all the entities in the "BLDNG (INN)" to quickly change color to all inns.

Sheets define the order in which they're drawn. Layers define a semantic label.

In some sense, yes. Just keep in mind that the selection interface works different for sheets and layers.

To select only entities in a given sheet, you'll have to hide every other sheet. But to select only on a given layer, you can either freeze every other layer or use the layer selection modifier:

Heh. I still mix them up.

Yup. I've been (slowly) reaching that conclusion. It was a long stretch, but worth trying nonetheless. Not all is lost though, I can still use Symbols in Area as Monsen suggested.

Though it must be said: it's still impressive to see that the backwards compatibility works as intended, flawlessly I'd say. And even the fact that FRIA didn't crash is outstansding (I once opened a Mike Schley map with FRIA by mistake, and even then it didn't crash. It still rendered the best it could).

Oh, don't tempt me. Lol. :)

I'm gonna be one of those guys who, after retirement, will still have something to do all day long.

Ralf did a live mapping session on creating your own symbols:

It starts describing how to create vector-based (very important to understand how symbol catalogs work), and then around 42:05 it covers importing PNGs as symbols.