Did you install 2016 version on the same machine where you had Cache 2014? For me, it looks like, the error on AutoCAD or Windows side, not on Caché side. But anyway I think you should ask for help in WRC.

You should look at the requirements part at this download Atelier page. Where you will see that Caché should be licensed.

Before doing such task, you should know a bit more about technologies which you going to use.
PDF - it is a binary format, so, you can't just copy text from PDF. Some of the files may contain a text, some just a picture with text.
And to get plain text from PDF, you have to use some third party OCR software. One of the leaders is ABBYY FineReader it is proprietary, but if you need you can find some products for free.

Looks like, it works exactly as LIST function in Caché

I would suggest that you have authorization in your web-application, and SoapUI fails to load it because it is not authorized.

follow the documentation and add it to the URL.

&CacheUserName=_SYSTEM&CachePassword=SYS

When you want to use Ensemble on Docker, it means that you need some integration with some external services. When you have to connect to some external services, no need any extra actions. But when you should use some shared folder, or some own internal services, which will be used by others, you have to expose some TCP ports, or volumes, and do some changes in a running process for this container. But you can use some network settings for the container, and in this case, Ensemble will be as a usual machine in your network, and you don't need to change any settings when you have to add some new internal service into Ensemble Production.
Windows also supports Docker but from version Server 2016. Windows also supports windows containers, but I don't know yet, is it supported to run windows version of Ensemble or not.

What you need to start your first Ensemble container within Ensemble application. The easiest way is to define some %Installer Manifest. When you can create a new database, load and compile your code, do some changes in an Ensemble settings.
There are some different examples of Dockerfile.
Quite simple, with only Ensemble. Or even with Apache inside, for some web application.

You can also look at this example of Dockerfile

### Cache ###
FROM tutum/centos:latest

MAINTAINER Dmitry Maslennikov <Dmitry.Maslennikov@csystem.cz>

# update OS + dependencies & run Caché silent instal
RUN yum -y update \
 && yum -y install which tar hostname net-tools wget \
 && yum -y clean all \ 
 && ln -sf /etc/locatime /usr/share/zoneinfo/Europe/Prague

ARG WRC_USERNAME
ARG WRC_PASSWORD
ARG cache=ensemble-2016.2.1.803.0
ARG globals8k=512
ARG routines=32
ARG locksiz=117964800

ENV TMP_INSTALL_DIR=/tmp/distrib

# vars for Caché silent install
ENV ISC_PACKAGE_INSTANCENAME="ENSEMBLE" \
    ISC_PACKAGE_INSTALLDIR="/opt/ensemble/" \
    ISC_PACKAGE_UNICODE="Y" \
    ISC_PACKAGE_CLIENT_COMPONENTS="" \

# vars for install our application     
    ISC_INSTALLER_MANIFEST=${TMP_INSTALL_DIR}/Installer.cls \
    ISC_INSTALLER_LOGFILE=installer_log \
    ISC_INSTALLER_LOGLEVEL=3 \
    ISC_INSTALLER_PARAMETERS="routines=$routines,locksiz=$locksiz,globals8k=$globals8k"

# set-up and install Caché from distrib_tmp dir 
WORKDIR ${TMP_INSTALL_DIR}

# our application installer
COPY Installer.cls .
# custom installation manifest 
COPY custom_install-manifest.isc ./$cache-lnxrhx64/package/custom_install/manifest.isc 
# license file
COPY cache.key $ISC_PACKAGE_INSTALLDIR/mgr/

# cache distributive
RUN wget -qO /dev/null --keep-session-cookies --save-cookies /dev/stdout --post-data="UserName=$WRC_USERNAME&Password=$WRC_PASSWORD" 'https://login.intersystems.com/login/SSO.UI.Login.cls?referrer=https%253A//wrc.intersystems.com/wrc/login.csp' \
 | wget -O - --load-cookies /dev/stdin "https://wrc.intersystems.com/wrc/WRC.StreamServer.cls?FILE=/wrc/distrib/$cache-lnxrhx64.tar.gz" \
 | tar xvfzC - . \
 && chmod +r ./$cache-lnxrhx64/package/custom_install/manifest.isc \
 && ./$cache-lnxrhx64/cinstall_silent custom_install \
 && cat $ISC_PACKAGE_INSTALLDIR/mgr/cconsole.log \
 && cat $ISC_PACKAGE_INSTALLDIR/mgr/installer_log \
 && ccontrol stop $ISC_PACKAGE_INSTANCENAME quietly \
 && rm -rf $TMP_INSTALL_DIR

# Caché container main process PID 1 (https://github.com/zrml/ccontainermain)
RUN curl -L https://github.com/daimor/ccontainermain/releases/download/0.1/ccontainermain -o /ccontainermain \
 && chmod +x /ccontainermain

# TCP sockets that can be accessed if user wants to (see 'docker run -p' flag)
EXPOSE 57772 1972 22

ENTRYPOINT ["/ccontainermain", "-cconsole", "-i", "ensemble"]

And installer manifest, with just some settings.

Class Temp.Installer 
{

XData setup [ XMLNamespace = INSTALLER ]
{
<Manifest>
  <If Condition='+"${routines}"=0'>
    <Var Name="routines" Value="32"/>
  </If>
  <If Condition='+"${globals8k}"=0'>
    <Var Name="globals8k" Value="256"/>
  </If>
  <If Condition='+"${locksiz}"=0'>
    <Var Name="locksiz" Value="1179648"/>
  </If>

  <SystemSetting 
    Name="Config.config.routines"
    Value="${routines}"/>

  <SystemSetting 
    Name="Config.config.globals8kb"
    Value="${globals8k}"/>

  <SystemSetting 
    Name="Config.config.locksiz"
    Value="${locksiz}"/>

</Manifest>
}

ClassMethod setup(
    ByRef pVars, 
    pLogLevel As %Integer = 3, 
    pInstaller As %Installer.Installer, 
    pLogger As %Installer.AbstractLogger
  ) As %Status [ CodeMode = objectgenerator, Internal ]
{
    do %code.WriteLine($char(9)_"set pVars(""CURRENTCLASS"")="""_%classname_"""")
    do %code.WriteLine($char(9)_"set pVars(""CURRENTNS"")="""_$namespace_"""")
  #; Let our XGL document generate code for this method. 
  Quit ##class(%Installer.Manifest).%Generate(%compiledclass, %code, "setup")
}

}

In this example, Ensemble distributive will be downloaded directly from the WRC.

to build this image

docker build -t ensemble --build-arg WRC_USERNAME=******* --build-arg WRC_PASSWORD=******* .

and to run the container from this image

docker run -p 57772:57772 ensemble

Most companies doing their backup over the network. It depends on how big your database, and you should estimate,  how quickly it will be in your case theoretical and in practice. Unfortunately, on some old versions of Caché, in some cases there are some lack of performance and backup may work not so fast as expected. We had such issue with 2012.2.

And a little hint, to do backup over the network, Caché instance should have an access. And if your Caché works on Windows, you should change user in settings for Caché Service, to some domain user, which will have access to write.