Error with psconvert on Example 2 Profilling

**Description of the problem**

I started using the GMTMEX on a windows computer. I start by running the examples from The GMT/MATLAB Toolbox 2017 paper. They all run as described except, for example 2 . When running the following line of code

I = gmt ('psconvert -TG -P -E300 -A', P);

I get the following error.

**Full error message**

```
psconvert [ERROR]: System call [@"C:\Program Files\gs\gs10.01.1\bin\gswin64c.exe" -q -dNOSAFER -dNOPAUSE -dBATCH -sDEVICE=bbox -DPSL_no_pagefill -dMaxBitmap=2147483647 -dUseFastColor=true "C:\Users\pdq\AppData\Local\Temp/psconvert_stream_13184.ps" 2> "./psconvert_13184c.bb"] returned error 1.
GMT: Module return with failure while executing the command
psconvert -TG -P -E300 -A
Error using gmtmex
GMT: exiting
```

I install the latest gs version, before I had the 9.2 version and I had the same error.

**Full script that generated the error**
Here is the full matlab script
```
clear; clc; close all
% Read in relief grid and Japan trench location
G = gmt ('read -Tg JP.nc');
T = gmt ('read -Td JP.txt');
% Take gradient in N45E direction to be used for illumination
intens = gmt ('grdgradient -Nt0.8 -A90', G);
% Sample grid along profiles normal to the trench
[profiles, stack] = gmt ('grdtrack -G -C300k/1k/25k -Sm+s+a', T, G);
% Evaluate an asymmetrical color palette with hinge at sealevel
C = gmt ('makecpt', '-Cgeo -T-8000/2000');
% Make the GMT plot
P = gmt ('grdimage', ['-R141/147/35/42 -JM6i -P -Baf -BWSne -I -K -C ' ...
'--FORMAT_GEO_MAP=dddF'], G, intens, C);
P = gmt ('pscoast', ['-R -J -O -K -W0.25p -Dh ' ...
'-LjTR+w200k+u+f+c38:30N+o0.5i/0.2i -F+gwhite+p0.5p']);
% Use first and last point of each profile and create a polygon of the area
A = gmt('convert', '-Ef -T', profiles);
B = gmt('convert', '-El -T -Is', profiles);
area = gmt ('catsegment', [A B]); % Join the two segments
P = gmt ('psxy', '-R -J -O -K -Ggreen@85', area);
P = gmt ('psxy -R -J -O -K -W2p+v0.3c+gred+p0.25p+bc+ec', T);
P = gmt ('psxy -R -J -O -K -W0.5p,red+v0.25c+p0.25p+bt+et', profiles);
P = gmt ('psscale', ['-R -J -O -DjBL+w3i/0.1i+h+o0.3i/0.4i -C -W0.001 ' ...
'-F+gwhite+p0.5p+i0.25p -Bxaf -By+l"km"'], C);

I = gmt ('psconvert -TG -P -E300 -A', P); % Windows Version

figure(1); clf
h = imshow (I.image); set (h, 'AlphaData', I.alpha)
% Figure 1 shows the stacked relief profiles across the trench
figure(2); clf; hold on
for k=1:length(profiles)
plot (profiles(k).data(:,3), profiles(k).data(:,5))
end
plot (stack.data(:,1), stack.data(:,2), 'LineWidth', 3)
xlabel('Distance (km)'); ylabel ('Depth (m)')
title ('Japan Trench Profiles'); xlim ([-150 150]); grid on
```

**System information**

* Operating system: Windows 10
* Version of GMT: GMT 6.4
* Version of GMTMex: Not sure of this, but I am assuming the latest from the GMT 6.4 version