Steam - Game crushes instantly (Mega Man Legacy Collection 2)

Problem: I try to run Mega Man Legacy Collection 2 on Steam (via Steam Play; Proton 4.2-2). Immediately after starting, the game crashes down. Disabling the in-game Steam Overlay in the game properties did not help.

I want to note that other games such as Counter-Strike: Source or Super Meat Boy work smoothly.

OS: Ubuntu 16.04.4 LTS
Kernel: 4.4.0-134-generic x86_64 (64 bit gcc: 5.4.0)
CPU: Dual core Intel Core i3-5010U (-HT-MCP-)
Graphics: Card: Intel Broadwell-U Integrated Graphics Display Server: X.Org 1.18.4 driver: intel Resolution: 1366x768@60.00hz GLX Renderer: Mesa DRI Intel HD Graphics 5500 (Broadwell GT2) GLX Version: 3.0 Mesa 18.0.5 Direct Rendering: Yes

I have found this (quite lengthy) crash-log:

Proton: 1553870914 proton-4.2-2
SteamGameId: 495050
Command: ['/home/my_username/.steam/steam/steamapps/common/MegaMan2/MMLC2.exe']

here are the error lines of it:

ERROR: ld.so: object '/home/my_username/.steam/ubuntu12_32/gameoverlayrenderer.so' from LD_PRELOAD cannot be preloaded (wrong ELF class: ELFCLASS32): ignored.
ERROR: ld.so: object '/home/my_username/.steam/ubuntu12_64/gameoverlayrenderer.so' from LD_PRELOAD cannot be preloaded (wrong ELF class: ELFCLASS64): ignored.
Fontconfig error: "/etc/fonts/conf.d/10-scale-bitmap-fonts.conf", line 72: non-double matrix element

Maybe the last line is also important:

pid 8324 != 8323, skipping destruction (fork without exec?)

I also want to mention that according to here , the first two errors can be ignored. Any ideas?

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