The Delphi documentation for MSBuild says
/property:name=value sets or overrides project-level properties, where name is the property name and value is t
You can find most of the parameters in the msbuild script C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\Borland.Delphi.Targets when you look at the CoreCompile target.
ExeOutput="$(DCC_ExeOutput)"
BplOutput="$(DCC_BplOutput)"
DcuOutput="$(DCC_DcuOutput)"
DcpOutput="$(DCC_DcpOutput)"
HppOutput="$(DCC_HppOutput)"
ObjOutput="$(DCC_ObjOutput)"
BpiOutput="$(DCC_BpiOutput)"
DependencyCheckOutputName = "$(DCC_DependencyCheckOutputName)"
UnitSearchPath="$(UnitSearchPath)"
ResourcePath="$(ResourcePath)"
IncludePath="$(IncludePath)"
ObjPath="$(_ObjectPath)"
UnitAlias="$(DCC_UnitAlias)"
ConsoleTarget="$(DCC_ConsoleTarget)"
Define="$(DCC_Define)"
FindError="$(DCC_FindError)"
MapFile="$(DCC_MapFile)"
Hints="$(DCC_Hints)"
CBuilderOutput="$(DCC_CBuilderOutput)"
BaseAddress="$(DCC_BaseAddress)"
UsePackage="$(_UsePackage)"
MakeModifiedUnits="$(DCC_MakeModifiedUnits)"
BuildAllUnits="$(DCC_BuildAllUnits)"
NameSpace="$(NameSpace)"
OldDosFileNames="$(DCC_OldDosFileNames)"
Quiet="$(DCC_Quiet)"
DebugInfoInExe="$(DCC_DebugInfoInExe)"
DebugVN="$(DCC_DebugVN)"
RemoteDebug="$(DCC_RemoteDebug)"
OutputNeverBuildDcps="$(DCC_OutputNeverBuildDcps)"
NoConfig="true"
OutputDRCFile="$(DCC_OutputDRCFile)"
OutputDependencies="$(DCC_OutputDependencies)"
OutputXMLDocumentation="$(DCC_OutputXMLDocumentation)"
DefaultNamespace="$(DCC_DefaultNamespace)"
Platform="$(DCC_Platform)"
UnsafeCode="$(DCC_UnsafeCode)"
Warnings="$(DCC_Warnings)"
Alignment="$(DCC_Alignment)"
MinimumEnumSize="$(DCC_MinimumEnumSize)"
FullBooleanEvaluations="$(DCC_FullBooleanEvaluations)"
AssertionsAtRuntime="$(DCC_AssertionsAtRuntime)"
DebugInformation="$(DCC_DebugInformation)"
ImportedDataReferences="$(DCC_ImportedDataReferences)"
LongStrings="$(DCC_LongStrings)"
IOChecking="$(DCC_IOChecking)"
WriteableConstants="$(DCC_WriteableConstants)"
LocalDebugSymbols="$(DCC_LocalDebugSymbols)"
RunTimeTypeInfo="$(DCC_RunTimeTypeInfo)"
Optimize="$(DCC_Optimize)"
OpenStringParams="$(DCC_OpenStringParams)"
IntegerOverflowCheck="$(DCC_IntegerOverflowCheck)"
RangeChecking="$(DCC_RangeChecking)"
TypedAtParameter="$(DCC_TypedAtParameter)"
PentiumSafeDivide="$(DCC_PentiumSafeDivide)"
StrictVarStrings="$(DCC_StrictVarStrings)"
GenerateStackFrames="$(DCC_GenerateStackFrames)"
ExtendedSyntax="$(DCC_ExtendedSyntax)"
SymbolReferenceInfo="$(DCC_SymbolReferenceInfo)"
StackSize="$(DCC_StackSize)"
ImageBase="$(DCC_ImageBase)"
Description="$(DCC_Description)"
DelaySign="$(DCC_DelaySign)"
KeyFile="$(DCC_KeyFile)"
KeyContainer="$(DCC_KetContainer)"
CodePage="$(DCC_CodePage)"
SYMBOL_DEPRECATED="$(DCC_SYMBOL_DEPRECATED)"
SYMBOL_LIBRARY="$(DCC_SYMBOL_LIBRARY)"
SYMBOL_PLATFORM="$(DCC_SYMBOL_PLATFORM)"
SYMBOL_EXPERIMENTAL="$(DCC_SYMBOL_EXPERIMENTAL)"
UNIT_LIBRARY="$(DCC_UNIT_LIBRARY)"
UNIT_PLATFORM="$(DCC_UNIT_PLATFORM)"
UNIT_DEPRECATED="$(DCC_UNIT_DEPRECATED)"
UNIT_EXPERIMENTAL="$(DCC_UNIT_EXPERIMENTAL)"
HRESULT_COMPAT="$(DCC_HRESULT_COMPAT)"
HIDING_MEMBER="$(DCC_HIDING_MEMBER)"
HIDDEN_VIRTUAL="$(DCC_HIDDEN_VIRTUAL)"
GARBAGE="$(DCC_GARBAGE)"
BOUNDS_ERROR="$(DCC_BOUNDS_ERROR)"
ZERO_NIL_COMPAT="$(DCC_ZERO_NIL_COMPAT)"
STRING_CONST_TRUNCED="$(DCC_STRING_CONST_TRUNCED)"
FOR_LOOP_VAR_VARPAR="$(DCC_FOR_LOOP_VAR_VARPAR)"
TYPED_CONST_VARPAR="$(DCC_TYPED_CONST_VARPAR)"
ASG_TO_TYPED_CONST="$(DCC_ASG_TO_TYPED_CONST)"
CASE_LABEL_RANGE="$(DCC_CASE_LABEL_RANGE)"
FOR_VARIABLE="$(DCC_FOR_VARIABLE)"
CONSTRUCTING_ABSTRACT="$(DCC_CONSTRUCTING_ABSTRACT)"
COMPARISON_FALSE="$(DCC_COMPARISON_FALSE)"
COMPARISON_TRUE="$(DCC_COMPARISON_TRUE)"
COMPARING_SIGNED_UNSIGNED="$(DCC_COMPARING_SIGNED_UNSIGNED)"
COMBINING_SIGNED_UNSIGNED="$(DCC_COMBINING_SIGNED_UNSIGNED)"
UNSUPPORTED_CONSTRUCT="$(DCC_UNSUPPORTED_CONSTRUCT)"
FILE_OPEN="$(DCC_FILE_OPEN)"
FILE_OPEN_UNITSRC="$(DCC_FILE_OPEN_UNITSRC)"
BAD_GLOBAL_SYMBOL="$(DCC_BAD_GLOBAL_SYMBOL)"
DUPLICATE_CTOR_DTOR="$(DCC_DUPLICATE_CTOR_DTOR)"
INVALID_DIRECTIVE="$(DCC_INVALID_DIRECTIVE)"
PACKAGE_NO_LINK="$(DCC_PACKAGE_NO_LINK)"
PACKAGED_THREADVAR="$(DCC_PACKAGED_THREADVAR)"
IMPLICIT_IMPORT="$(DCC_IMPLICIT_IMPORT)"
HPPEMIT_IGNORED="$(DCC_HPPEMIT_IGNORED)"
NO_RETVAL="$(DCC_NO_RETVAL)"
USE_BEFORE_DEF="$(DCC_USE_BEFORE_DEF)"
FOR_LOOP_VAR_UNDEF="$(DCC_FOR_LOOP_VAR_UNDEF)"
UNIT_NAME_MISMATCH="$(DCC_UNIT_NAME_MISMATCH)"
NO_CFG_FILE_FOUND="$(DCC_NO_CFG_FILE_FOUND)"
IMPLICIT_VARIANTS="$(DCC_IMPLICIT_VARIANTS)"
UNICODE_TO_LOCALE="$(DCC_UNICODE_TO_LOCALE)"
LOCALE_TO_UNICODE="$(DCC_LOCALE_TO_UNICODE)"
IMAGEBASE_MULTIPLE="$(DCC_IMAGEBASE_MULTIPLE)"
SUSPICIOUS_TYPECAST="$(DCC_SUSPICIOUS_TYPECAST)"
PRIVATE_PROPACCESSOR="$(DCC_PRIVATE_PROPACCESSOR)"
UNSAFE_TYPE="$(DCC_UNSAFE_TYPE)"
UNSAFE_CODE="$(DCC_UNSAFE_CODE)"
UNSAFE_CAST="$(DCC_UNSAFE_CAST)"
OPTION_TRUNCATED="$(DCC_OPTION_TRUNCATED)"
WIDECHAR_REDUCED="$(DCC_WIDECHAR_REDUCED)"
DUPLICATES_IGNORED="$(DCC_DUPLICATES_IGNORED)"
UNIT_INIT_SEQ="$(DCC_UNIT_INIT_SEQ)"
LOCAL_PINVOKE="$(DCC_LOCAL_PINVOKE)"
MESSAGE_DIRECTIVE="$(DCC_MESSAGE_DIRECTIVE)"
TYPEINFO_IMPLICITLY_ADDED="$(DCC_TYPEINFO_IMPLICITLY_ADDED)"
XML_WHITESPACE_NOT_ALLOWED="$(DCC_XML_WHITESPACE_NOT_ALLOWED)"
XML_UNKNOWN_ENTITY="$(DCC_XML_UNKNOWN_ENTITY)"
XML_INVALID_NAME_START="$(DCC_XML_INVALID_NAME_START)"
XML_INVALID_NAME="$(DCC_XML_INVALID_NAME)"
XML_EXPECTED_CHARACTER="$(DCC_XML_EXPECTED_CHARACTER)"
XML_CREF_NO_RESOLVE="$(DCC_XML_CREF_NO_RESOLVE)"
XML_NO_PARM="$(DCC_XML_NO_PARM)"
XML_NO_MATCHING_PARM="$(DCC_XML_NO_MATCHING_PARM)"
So to set the defines you could use the DCC_Define parameter like this:
msbuild yourproject.dproj /p:DCC_Define=MY_DEFINE
Others you will find in the .dproj file of your project
<Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
<Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
So it is Configuration and not Config. At least in Delphi 2007.
You might want to learn more about msbuild in general to understand the scripts better and learn how you could make your own msbuild scripts to drive a build machine.
Disclaimer: This information is from a Delphi 2007 setup