German is no problem for me! I found an issue with MCTS=1 search:
[fen]4Kb2/5Np1/2p1k1p1/2p5/2PpNnP1/2PP3p/4n3/2rbr1B1 w - - 0 1[/fen]
Analysis by ShashChess 20.2:
1.Nd8+ Ke5 2.Nf7+ Ke6
= (0.00) Depth: 7/7 00:00:00 8kN
1.Nd8+ Ke5 2.Nf7+ Ke6 3.Nd8+
= (0.00) Depth: 8/7 00:00:00 10kN
1.Nd8+ Ke5 2.Nf7+ Ke6 3.Nd8+
= (0.00) Depth: 9/6 00:00:00 12kN
1.Nd8+ Ke5 2.Nf7+ Ke6
= (0.00) Depth: 10/5 00:00:00 13kN
1.Nd8+ Ke5 2.Nf7+ Ke6 3.Nd8+
= (0.00) Depth: 11/6 00:00:00 28kN
1.Nd8+ Ke5 2.Nf7+ Ke6 3.Nd8+
= (0.00) Depth: 12/6 00:00:00 53kN
1.Nd8+ Ke5 2.Nf7+ Ke6 3.Nd8+
= (0.00) Depth: 13/6 00:00:00 91kN
1.Nd8+ Ke5 2.Nf7+ Ke6
= (0.00) Depth: 14/5 00:00:00 103kN
1.Nd8+ Ke5 2.Nf7+ Ke6 3.Nd8+
= (0.00) Depth: 15/6 00:00:00 128kN
1.Nd8+ Ke5 2.Nf7+ Ke6
= (0.00) Depth: 16/5 00:00:00 183kN
1.Nd8+ Ke5 2.Nf7+ Ke6 3.Nfg5+ Ke5
= (0.00) Depth: 17/7 00:00:00 221kN
1.Nd8+ Ke5 2.Nf7+ Ke6 3.Nd8+
= (0.00) Depth: 18/6 00:00:00 264kN
1.Nd8+ Ke5 2.Nf7+ Ke6
= (0.00) Depth: 19/5 00:00:00 320kN
1.Nd8+ Ke5 2.Nf7+ Ke6 3.Nd8+
= (0.00) Depth: 20/6 00:00:00 348kN
1.Nd8+ Ke5 2.Nf7+ Ke6
= (0.00) Depth: 21/5 00:00:00 466kN
1.Nfg5+ Ke5 2.Nf3+
+- (#2) Depth: 22/5 00:00:00 868kN
1.Nfg5+ Ke5 2.Nf7+
+- (#2) Depth: 23/6 00:00:00 924kN
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 24/6 00:00:00 942kN
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 25/5 00:00:00 943kN
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 26/5 00:00:00 943kN
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 27/5 00:00:00 943kN
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 28/5 00:00:00 943kN
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 29/5 00:00:00 944kN
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 30/6 00:00:00 944kN
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 31/5 00:00:00 960kN
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 32/6 00:00:00 987kN
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 33/5 00:00:00 1018kN
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 34/6 00:00:00 1052kN
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 35/6 00:00:00 1120kN
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 36/6 00:00:00 1202kN
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 37/6 00:00:00 1279kN
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 38/5 00:00:00 1360kN
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 39/6 00:00:00 1428kN
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 40/5 00:00:00 1510kN
1.Neg5+ Kf6 2.Ne4+ Ke6 3.Nfg5+
+- (#3) Depth: 41/5 00:00:00 1600kN
1.Neg5+ Kf6 2.Nh7+
+- (#2) Depth: 42/5 00:00:00 8660kN, tb=66
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 43/30 00:00:02 26270kN, tb=525
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 44/6 00:00:02 26270kN, tb=525
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 45/5 00:00:02 26271kN, tb=525
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 46/6 00:00:02 26271kN, tb=525
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 47/5 00:00:02 26271kN, tb=525
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 48/6 00:00:02 26271kN, tb=525
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 49/5 00:00:02 26271kN, tb=525
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 50/6 00:00:02 26272kN, tb=525
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 51/5 00:00:02 26272kN, tb=525
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 52/6 00:00:02 26272kN, tb=525
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 53/5 00:00:02 26272kN, tb=525
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 54/6 00:00:02 26272kN, tb=525
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 55/6 00:00:02 26273kN, tb=525
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 56/6 00:00:02 26484kN, tb=528
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 57/5 00:00:03 31105kN, tb=828
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 58/5 00:00:03 31145kN, tb=828
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 59/5 00:00:03 31157kN, tb=828
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 60/5 00:00:03 31876kN, tb=835
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 61/6 00:00:03 34160kN, tb=977
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 62/5 00:00:03 34602kN, tb=978
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 63/5 00:00:04 40351kN, tb=2082
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 64/5 00:00:04 42347kN, tb=2246
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 65/6 00:00:04 43835kN, tb=2456
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 66/5 00:00:05 49924kN, tb=3221
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 67/5 00:00:05 51053kN, tb=3256
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 68/5 00:00:05 52023kN, tb=3544
1.Neg5+ Kf6 2.Ne4+
+- (#2) Depth: 69/6 00:00:05 53591kN, tb=4048
5 cores used. Weird

. Position is mate in 15. BTW this happens only sometimes and in Chessbase GUI.